A. According to the graph, are John and Collin saving or spending money? a. Saving
b. Spending
c. Idunno

B. How much money did each person start with?
a. John 60, Collin 80
b. John 80, Collin 60
c. John 4, Collin 6
d. Collin 6, John 4

C. How many days does it take John to spend all his money?

D. How many days does it take Collin to spend all his money?

E. Find the solution to the above system (answer is on ordered pair):

F. At what day does John and Collin have the same amount of money? Day

G. On the day they they have the same amount of money, how much do they each have? _ dollars

Ariana starts with 100 milligrams of a radioactive substance. the amount of the substance decreases by 20% each week for a number of weeks, w. the expression 100(1−0.2)w finds the amount of radioactive substance remaining after w weeks. which statement about this expression is true? a) it is the difference between the initial amount and the percent decrease. b) it is the difference between the initial amount and the decay factor after w weeks. c) it is the initial amount raised to the decay factor after w weeks. d) it is the product of the initial amount and the decay factor after w weeks.