An oil bath maintained at 40°C with a convective coefficient 500 W/m2·K is used to quench stainless steel spherical ball bearings ( 25 W/m·K, 4.85 x 10-6 m2/s) in order to harden them. Consider a ball bearing of uniform temperature 850°C and a diameter of 40 mm. How long, in seconds, will it take for the surface temperature of the sphere to reach 100°C? What is the corresponding center temperature, in °C?

Inner peace.. jk it's  a stable electron configuration

W= fd
where f is an applied force and d is the distance over which it is applied. when a parachuting skydiver is at constant velocity, he is experiencing "terminal velocity", the point at which his acceleration down is canceled out by air resistance. that means that the resisting force of the air is equal to his weight, but in the opposite direction. with this, we can solve for the work done by the force.
w = fd
w = (92.0)(9.81 m/s^2) (325)
w= 2.93 x 10^5 j
the value for work in this case is positive because it is pushing up on the skydiver, who has a downward force of gravity.
therefore the answer is 2.93 x 10^5 j

It really doesn't matter for any of the questions that you've listed.

Answer it orbits high above earth to gain clearer images of light, it magnifies images relative to the human eye, it records most of the universe as it was in the past, not as it is now;