When a 1 kg ball is dropped from the roof of a building its speed increases from 0 m/s to 10 m/s just before it hits the ground. what is the ball's change in kinetic energy at its maximum (fastest) speed?

it's c (engineer's do their work with mechanical stuff not on any living being)

answer: semi-infinite solid initially at a uniform temperature of 400 ◦c is cooled at its surface by convection. the cooling fluid at a constant temperature of 200 ◦c has a convective coefficient (ha) of 250 w/m2.k. the physical properties of the solid: k = 20 w/m.k and α = 4 * 10-5  m2/s. using δx = 0.04 m and δt = 10 s. write the finite difference equations describing the transient heat transfer of the first five δx and the temperature profile after 30 s.