Marsha waite borrows $7,000 and agrees to pay it back in 2 years if the simple interest rate is 15%

Marsha must pay in 2 years

Step-by-step explanation:

we know that

The simple interest formula is equal to

where

A  is the amount of money to pay

P is amount of money borrowed  

r is the rate of interest  

t is Number of Time Periods

in this problem we have

substitute in the formula above

therefore

Marsha must pay in 2 years

its a straight line parallel to the time axis

b) 1/3 * 1/5

step-by-step explanation:

each smallest part is 1/15 since the written one is 1/5 and it's divided by 3 equal parts. (1/5 )/3 = 1/15 = 1/3 * 1/5