Choosing Linear Quadratic or Exponential Model

Write an equation that models the following situation:
Samantha's hair was known to grow very rapidly. It began at a length of 6 in and grew at a rate of 14% a week.

• y=6(0.14)^x

• y=6(1+14)^x

• y=6(1.14)^x

• y=6(0.86)^x

Is the equation linear, exponential or neither?

• Linear

• Exponential

• Neither

Bacteria can multiply at an alarming rate when each bacteria splits into two new cells, thus doubling. If we start with only one bacteria which can double every hour, which equation can be used to represent the number of bacteria after x hours?

• y=x²

• y=1(2)^x

• y=(1/2)^x

• y=2(1)^x

The southern white rhinoceros reproduces roughly once every 3 years, giving birth to one calf each time.  Suppose that a nature preserve houses 100 white rhinoceroses, 50 of which are female.  Assume that half of the calves born are female and that females can reproduce as soon as they are 1 year old.
What type of a function should be used to model the population of female white rhinoceroses in the preserve?

• Linear function

• Exponential function

• Quadratic function

• Cubic function

What function model best represents the data in the table?

• linear

• exponential

• quadratic

• A

• B

• C

• D

Which equation best fits the data in the table?

• y = 15940x - 2423.6

• y = 267.71x² -3494.46 + 16500

• y = 16500(0.80)^x

What model best represents that data.

• quadratic

• exponential

• trigonometric

• linear

Leonard compared the cost of purchasing a gallon of gas at two different gas stations. The function C(g) = 3.25 + 0.07x models the average cost of a gallon of gas at the first gas station after x months. The table below shows the average cost of a gallon of gas at the second gas station after different numbers of months. Which statement is true?

• The first station had a higher initial price per gallon and increased at a greater amount per month than the second station.

• The second station had a higher initial price per gallon and increased at a greater amount per month than the first station.

• The first station had a higher initial price per gallon but increased at a smaller amount per month than the second station.

• The second station had a higher initial price per gallon but increased at a smaller amount per month than the first station.

A chemist has a 100-gram sample of a radioactive material.  He records the amount of radioactive material every week for 6 weeks and obtains the following data: Find the exponential model of the function.

• y = 100(8.7)^x

• y = 100(1.87)^x

• y = 100(.87)^x

• y = 100(.13)^x