Answer:
30000 feet
Step-by-step explanation:
temperature on ground level = 65 °F
temperature at cruising altitude = -43 °F
total decrease in temperature = 65 - (- 43) = 65 + 43 = 108 °F
for each 1000 feet elevation temperature drops by 3.6 °F
and we have the total drop of temperature as 108 °F.
so, Height of plane at cruising altitude = (drop in temperature/ 3.6) X 1000
=
= 30000 feet