In the table, x represents minutes, and y represents the altitude of an airplane.
table
x y
15 22,500
20 20,000
25 17,500
30 15,000
which statement is correct about the slope of the linear function that the table represents?
a. the slope is positive because as the minutes decrease, the altitude increases.
b. the slope is positive because as the minutes increase, the altitude increases.
c. the slope is negative because as the minutes decrease, the altitude decreases.
d. the slope is negative because as the minutes increase, the altitude decreases.