A double-pane insulated window unit consists of two 1-cm-thick pieces of glass separated by a 1.8-cm layer of air. The unit measures 4 m in width and is 3 m wide. Under conditions where the extreme outside temperature of the glass is at −10∘C and air, at 27∘ C, is adjacent to the inside glass surface, with hi=12W/m2⋅K, determinea. the inside glass surface temperatureb. the rate of heat transfer through the window unitThe air gap between glass panes may be treated as a purely conductive layer with k=0.0262W/m⋅K. Thermal radiation is to be neglected.

answer: the exterior temperature of commercial jet planes as they leave the stratosphere and return to the ground increases steadily.

explanation:

the lower most layer of atmosphere is troposphere which extends from 0 to 12 km above the surface of the earth. the temperature initially decreases as distance is increased from the earth's surface. commercial jets fly in lower part of the stratosphere. the stratosphere extends upto 50 km. the temperature in stratosphere starts rising again due to presence of ozone which traps the uv rays.

thus, when the planes leave the stratosphere and return to the ground, the exterior temperature increases steadily.

it has to be b, about 97 percent.