You can't see beyond a blind turn, so a mirror would allow you to see around the corner.
Answer:1200
Explanation:
Given data
Upper Temprature
Lower Temprature 
Engine power ouput
Efficiency of carnot cycle is given by





rounding off to two significant figures

There is no definite end to earths atmosphere, but technically the border between the outer space and earth gets thinner as you move up from the earths surface. The Karman line is the closest definition there is which describes the end of the earth's atmosphere, it is 100 km above earth's sea level at approximately 1.56 % of total earth's radius. This describes the boundary between the outer space and the atmosphere.