Celina and Richard spend a certain amount of money from their money box each month to buy plants. The table shows the relationship between the amount of money (y) remaining in Celina's money box and the number of months (x):

Function 1:

Number of Months
(x) Amount Remaining (dollars)
(y)
1 20
2 18
3 16
4 14

The equation shows the relationship between the amount of money, y, remaining in Richard's money box and the number of months, x:

Function 2:
y = –6x + 20

Which statement explains which function shows a greater rate of change?
Function 2 shows a greater rate of change, because Richard spends $20 each month and Celina spends $6 each month.
Function 1 shows a greater rate of change, because Celina spends $6 each month and Richard spends $14 each month.
Function 1 shows a greater rate of change, because Celina spends $2 each month and Richard spends –$6 each month.
Function 2 shows a greater rate of change, because Richard spends $6 each month and Celina spends $2 each month.