When can you use proportional reasoning to solve a problem? A: When two quantities add to 1 B: When one quantity is a constant multiple of the other C: When the two quantities multiplied equal a constant D: When one quantity is 1 more than the other

B: When one quantity is a constant multiple of the other

Step-by-step explanation:

soo this can be solve by using the formula:

f = p( 1 + i)^ n

where f is the future profit

p is the initial profit

i is the percent increase

n is the number of years

a . f = 30000 ( 1.05)^n

b. f = 30000 ( 1.05)^15

f = $62,368