Explain why the several different types of microscopes are all neccassary?

Aballet student who learns with the of his instructor is demonstrating learning.

Ball bearings are made by letting spherical drops of molten metal fall inside a talll tower-called a shot tower- and solidify as they fall. a-if a bearing needs 4.0 s to solidify enough for impact, how high must the tower be? b- what is the bearing's impact velocity?

Question 1(multiple choice worth 2 points) in order to be considered work, the components that must be present are • a force and a movement in the same direction as the force an action which causes movement and an opposite reaction an action which causes no movement or reaction a force and a movement in the opposite direction of the force