9514 1404 393
Answer:
D. -2.09 degrees per minute
Step-by-step explanation:
The average rate of change is the change in temperature divided by the change in time:
m = (T(30) -T(10))/(30 -10)
= ((15 +155 e^(-30·0.02)) -(15 +155 e^(-10·0.02))/20
= (155/20)(e^-0.6 -e^-0.2) ≈ -2.09 . . . degrees per minute