After the last ice age began, the number of animal species in Australia changed rapidly.

The relationship between the elapsed time, t, in years, since the ice age began, and the total number of animal species, S(t), is modeled by the following function:
S(t)=4,200,000⋅(0.72)t

Complete the following sentence about the yearly percent change of the number of animal species.

Every year, _______ percent of species are SUBTRACTED/ADDED from the total number of animal species.

Answers

Answer 1

Answer:

Every year 28 percent of species are SUBTRACTED from the total number of animal species.

Step-by-step explanation:

Exponential growth or decay:

The equation for exponential growth or decay has the following format:

[tex]A(t) = A(0)(1+r)^t[/tex]

In which A(0) is the initial amount and r is the growth/decay rate, as a decimal.

If r > 0, each year r percent is added to the total number, and if r < 0, each year, r percent is decreased from the total number.

In this question:

[tex]S(t) = 4200000(0.72)^t[/tex]

So

[tex]1 - r = 0.72[/tex]

[tex]r = 0.72 - 1 = -0.28[/tex]

Thus

Every year 28 percent of species are SUBTRACTED from the total number of animal species.


Related Questions

Solve this 6 - 4(3 - 6x) + 12x

Answers

Answer:

Step-by-step explanation:

Mr. and Mrs. Doran have a genetic history such that the probability that a child being born to them with a certain trait is 2/5. If they have three children, what is the probability that exactly three of their three children will have that trait? Round your answer to the nearest thousandth.

Answers

Answer:

any details?

Step-by-step explanation:

If 154 pounds is the lightest weight, then
pounds is the heaviest.
170
163
169

Answers

Answer:

169 Pounds

Step-by-step explanation:

...

169 pounds is the answer

Use a permutation expression to solve.

In a race of 39 people, how many different ways can the runners place in 1st, 2nd, and 3rd?

9,139

18,278

54,834

59,319

Answers

Answer:

C. 54,834

Step-by-step explanation:

Took the test

Which of the following graphs is the same as y = log1/2x?

Answers

Answer:

x=2^-y

A

Step-by-step explanation:

x | y

1 | 0

2 | -1

4 | -2

Jill owe $4 dollars to Jennifer, $4 to Michelle, and $4 to Eileen. How much does she owe altogether?

Answers

Answer:

12

Step-by-step explanation:

4+4+4=12 :)

Answer:12

Step-by-step explanation:

Help pls I’ll give extra pointz

Answers

Answer:

The answer is (A) decreases

Expand and simplify (2x + 1)(x + 3)

Answers

expand and simplify (2x + 1)(x + 3)

answer : [tex]2x^2+7x+3[/tex]

-

explanation : expand the polynomial using the FOIL method.

-

FOIL : a technique for distributing two binomials. the letters FOIL stand for first, outer, inner, last. first means multiply the terms which occur first in each binomial, outer means multiply the outermost terms in the product, inner means multiply the innermost terms, and last means multiply the terms which occur last in each binomial.

-

step 1 : multiply each term in the first parentheses by each term in the second parentheses (FOIL)

ex : [tex]2x * x+2x * 3+x+3[/tex]

step 2 : calculate the product

ex: [tex]2x^2+2x * 3+x+3[/tex]

step 3 : calculate the product

ex: [tex]2x^2+6x+x+3[/tex]

step 4 : collect like terms

ex: [tex]2x^2+7x+3[/tex]

-

solution : [tex]2x^2+7x+3[/tex]

hope this helps !

- audrey ♡

This figure shows an oblique triangle-based pyramid.
What is the volume of the figure?

Answers

Answer: 88 cm^3

Step-by-step explanation:

= 1/2 • bh

= 1/2 • 6 • 8

= 24

= 1/3 • 24 • 11

= 88 cm^3

The volume of the oblique triangle-based pyramid, having dimensions 6 cm, 8 cm, 11 cm, and 36.2 cm, is 88 cm³.

What is volume?

The capacity occupied by a three-dimensional solid shape is known as volume. It is difficult to visualize in any shape, yet it may be compared among shapes. For instance, a compass box has a larger volume than an eraser placed inside of it.

Given:

The dimension of the pyramid are 6 cm, 8 cm, 11 cm, and 36.2 cm,

Calculate the volume as shown below,

The Volume of the pyramid = 1 / 3 × Area of the triangle × height

The volume of the pyramid =  1 / 3 × 1 / 2 × 6 × 8 × 11

The volume of the pyramid = 528 / 6

The volume of the pyramid = 88

Thus, the volume of the pyramid is 88 cm³.

To know more about volume:

brainly.com/question/13807002

#SPJ2

Determine whether the following study is an observational study or an experiment. If the study is an experiment, identify the control and treatment groups, and discuss whether single- or double-blinding is necessary. If the study is observational, state whether it is a case-control study, and if so, identify the cases and controls.
In a study of the effects of magnets on back pain, some participants were treated with magnets while others were given nonmagnetic objects with a similar appearance. The magnets did not appear to be effective in treating back pain. Choose the correct answer below.
A. Experiment, the treatment group is patients that used the magnets and the control group is patients that received the placebo; double blind
B. Observational study; case control; the cases are the patients that received magnets, the controls are the patients that received placebos
C. Observational study; not case-control
D. Experiment, the treatment group is all patients and the control group is patients that received the magnets; single blind

Answers

Answer:

A. whether a woman took hormones.

B. whether to woman in the study had a heart attack.

D. access to health care

Step-by-step explanation:

The study conducted to observe the menopausal woman must be supported with their health history. Some woman may have menopause at an early age while other go towards this at a later age. This can be due to smoking, hormone intake, severe diseases like heart attack or cancer and their routine health checkup details. There variables must be observed and included in experiment to reach a conclusion.

WILL




GIVE


BRAINLIST ANSWER

.

..
.
.
.

Answers

the answer 1/6 because a die has 6 sides and you are only wanting 1 number so the chances are 1/6

Use I = PRT to find the total amount in the savings account.
$1555.00 at 8% for 2 years
PLEASE HELP ASAP​

Answers

Answer:

[tex]\boxed {\boxed {\sf \$ 1803.80}}}[/tex]

Step-by-step explanation:

We are using the formula I=PRT and calculating simple interest.

[tex]I=PRT[/tex]

I is the interest, P is the principal or starting amount, R is the interest rate as a decimal, and T is the time in years.

We know that there is $1555.00 at 8% for 2 years. First, convert the interest rate to a decimal. Divide the rate by 100 or move the decimal place 2 spots to the left.

8/100 = 0.08 8. --> 0.8  --> 0.08

Now we know all the values:

P= 1555.00 R= 0.08T= 2

Substitute the values into the formula.

[tex]I= (1555.00)(0.08)(2)[/tex]

Multiply.

[tex]I=124.4(2)[/tex]

[tex]I=248.8[/tex]

The account earned $248.80 in interest, but the question asks for the total amount in the account. We must add the interest to the starting amount.

[tex]1555.00 +248.80[/tex]

[tex]1803.8[/tex]

After 2 years, the savings account had $1803.80

Step-by-step explanation:

Principal=P=1555

Rate of Interest=I=8%=0.08

Time=t=2

Interest=I=PRT

➜1555×0.08×2

➜248.8

Savings=P+I

➜1555+248.8

➜1803.8

A smartphone costs $250. Sales tax is 7%. What is the total cost, including tax?
The cost of the smartphone, with tax, is $

Answers

Answer:17.5

Step-by-step explanation:

Our output value is 250

We represent the unknown value wit “x”

250= 100%

x= 7%

By dividing equation 1 by equation 2 and noting that both the RHS (right hand side) of both

equations have the same unit (%); we have

250/x = 100%/7%

Again, the reciprocal of both sides gives

x/250= 7/100

X= 17.5

17.5=7% of 250

Which statements about this system of equations are true? Check all that apply 2 x minus 7 y = negative 13. Negative 2 x + 11 y = 1. The x-variable will be eliminated when adding the system of equations. The y-variable will be eliminated when adding the system of equations. The sum of the system of equations is 4 y = negative 12. x = 17 y = negative 3 There are infinitely many solutions to the system of equations.

Answers

Answer:

• The x-variable will be eliminated when adding the system of equations.

• The sum of the system of equations is 4y = -12

Step-by-step explanation:

2x - 7y = -13

-2x + 11y = 1

---------------------

Adding the equations

4y = -12

y = -3

x = -17

-----------------------

• The x-variable will be eliminated when adding the system of equations.

• The sum of the system of equations is 4y = -12

Answer:

The correct answer is A and C

Step-by-step explanation:

I took the test and got 100%

(5) 60% of a number is 36. Use this fact to find:
a) 30% of the number
b) 20% of the number.
c) 50% of the number​

Answers

Answer:

The number is 60

a) 18

b)12

c) 30

Step-by-step explanation:

Find the mode of the data.
1, 2, 1, 3, 3, 4, 1
The mode is

Answers

Answer:

1 is the answer.

Step-by-step explanation:

The mode of a data set is the number that occurs most frequently in the set.

Kong took 15%, percent fewer seconds than Nolan took to complete his multiplication timed test. Kong took 85 seconds.
How many seconds did Nolan take?

Answers

Answer:

Step-by-step explanation:

Which means that Nolan took 100 seconds. This is all from Khan Academy so it's correct!!

256-x²/4
factorise in process​

Answers

Answer:

[tex]16^2-(\dfrac{x}{2})^2=(16+\dfrac{x}{2})(16-\dfrac{x}{2})[/tex]

Step-by-step explanation:

The given expression is : [tex]256-\dfrac{x^2}{4}[/tex].

We need to factorize it.

We know that, 16² = 256

So,

[tex]256-\dfrac{x^2}{4}=(16)^2-(\dfrac{x}{2})^2[/tex]

We know that, [tex]a^2-b^2=(a-b)(a+b)[/tex]

[tex]16^2-(\dfrac{x}{2})^2=(16+\dfrac{x}{2})(16-\dfrac{x}{2})[/tex]

Hence, this is the required solution.

Find the area of the following figure and write your result in the empty box.

Answers

Answer:

Area = 406

Step-by-step explanation:

First things first: Divide the shape

Here is how I did it:

21 x 16

14 x 5

Now solve:

21 x 16 = 336

14 x 5 = 70

Now add:

336 + 70 = 406

So the area is 406

Find the area of each shape. Include units in your answer. Show your work. Section 1 worth 5 points. Section 2 worth 15 points.

Answers

Answer:

Step-by-step explanation: can you add a picture of the problem?

I need help on this!!

Study guide for exam

The circle have the same question.

No links

Answers

Answer: Picture pls

Step-by-step explanation:

.

Answer:
What’s the question

Explanation:

When Rashaad goes bowling, his scores are normally distributed with a mean of 175
and a standard deviation of 13. Using the empirical rule, determine the interval that
would represent the middle 68% of the scores of all the games that Rashaad bowls.

Answers

Answer:

The interval (162, 188)would represent the middle 68% of the scores of all the games that Rashaad bowls.

Step-by-step explanation:

As per the  empirical rule of normal distribution, for any normally distributed curve, the values lie between the extreme values i.e  

(μ - σ) and (μ + σ).

Given  

μ  = 175

σ = 13

(μ - σ) = 175 -13 = 162

(μ + σ) = 175 + 13 = 188

Hence the required interval is 162, 188

What is the correct answer?? I will mark as brainlest

Answers

Answer: t=0.15n

Step-by-step explanation:

Line A passes through the point (-8, 3) and is perpendicular to the line represented by the equation
y = -4x + 9. Line A can be expressed as an equation of the form y = mx + b.
Part A
What is the value of m for line A?
Part B
What is the value of b for line A?

Answers

Answer:

Did u get the answers ?

Step-by-step explanation:

I need help lol

Answer: A: -4 B:-29

Step-by-step explanation:

what is 120 ratio 5:7​

Answers

Answer:

50

Step-by-step explanation:

Can someone please help me with both I will mark u brilliant

Answers

Answer: Question 5 is 18

Question 6 is 11

Step-by-step explanation:

Find the value of the expression 3+4r+n3 n=1 and r=2

Answers

Answer:

14

Step-by-step explanation:

I'll show you how I did it.

3+4r+n3=?

3+(4*r)+(n*3)=?

3+8+3=?

11+3=14

if a 48-gram serving of pasta contains 6 g of protein how many grams of protein are in a 1,362 gram box of pasta

Answers

Answer:

170.25 grams of protein

Step-by-step explanation:

6/48 = p/1362

cross multiply

6 x 1362 = 48p

8172 = 48p

isolate variable (p) with division

8172/48 = p

170.25 = p

Which are elements and geographical skills in which can be applied in one's life as practical or professional?

Answers

Answer:

using a map is a geographical skill in everyday life.

Step-by-step explanation:

PLEASE HELP ME ASP !!

Answers

Answer:

B

Step-by-step explanation:

if its a straight line, then just subtract from 180

180 - 84 = 96

EAT MY SANDWICH ANX YH
Other Questions
good research should ideally be... (5^2 10) 5 2^3? i know its 24 but can someone please explain it to me? How do lenders make money when giving out loans ? A) principals B) credit rates C) interest rates D) federal reserve What equation represents the proportional relationship displayed in the table?x 2 4 6 8y 10 20 30 40Enter your answer by filling in the box to complete the equation. Air entrainment is used in concrete to: __________.1. Strengthen the concrete 2. Increase the resistance of the concrete to freeze thaw damage 3. Create a better surface appearance 4. Make the concrete easier to handle during placement 5. Help evaporate excess water from the curing concrete What does the revolver do?sends the domain name and requests the IP addresssends the IP address and requests the content of the web pagesends the IP address and requests the domain namesends the domain name and requests the content of the web page defintion of Symmetrical Dot Plot explica cmo una flor se convierte en fruta Describe the psychological impact of the slave trade on Africans. Hey, can I get help with this question?:Write an expression that simplifies to [tex]x^{3}[/tex] using the Quotient of Powers Property. What did Percival Lowell build in Flagstaff, Arizona? A. an observatory B. a university C. an architecture school D. an airplane factory Whats the difference between poetry and prose? In your own words b. Earth's thermohaline circulation moves heat around the planet, as can be seen by the warmerclimate in England due to the Gulf Stream. (2 points)True or false ? Hi I need help in those two questions please don't type something that doesn't make sense for the points and have a good day Which of the following is made of cells?1. ocean water2. glass bowl3.oak tree4. cement sidewalk Who is the most inspirational female (someone famous or well known) to you and why? Anybody wanna support some rap music? Check me out tell me what y'all think. Which table of ordered pairs matches the following function?2y + 8x = 2 MNOP is trapezium. The distance between MN and PQ is 21cm and MN= 28cm, while PQ= 25cm. Find the area. TOPIC TEST TIMED 10 POINTSWhich of the following actions might be part of a protectionist economic policy?A.reducing barriers to tradeB.signing free trade agreementsC.cutting tariffs on imported goodsD.establishing quotas on imports