Answer:c>a>b
Explanation:
Given
All the engine extracts same amount of heat(Q) from High-temperature reservoir
For a) 400 and 500 K




For b)500 K and 600K


For c) 400 K and 600 K


So c will give the highest amount of work
c>a>b
According to my research, Friction is bad when you get blisters that's when it can be harmful.
Answer:
less than one light year. We would all be dead if it was more than a light year.
Answer: They’d fall at the same speed, because air resistance is the only thing that makes an object fall faster than another. There’s a video somewhere on the internet of a bowling ball and a feather falling at the same speed in a vacuum, if you look for it. Hope this helps!
Answer:
Truck will be at a distance of 720 m
Explanation:
Speed of the truck is given as 90 m/sec
Time for which truck travel t = 10 seconds
We have to find the distance that how much truck travel in 8 sec with speed of 90 m/sec
We know that distance is given by 
So distance traveled by truck in 8 sec will be equal to 
So truck will be at a distance of 720 m