Calculate the frequency of photon 434e-9 and speed of light 3e8m/s

Why does the input force have to be greater than the force needed to lift the bale?

Will you chech and finish these for me, because i am stumped with them.

Total solidification times of three casting geometries are to be compared: a sphere, a cylinder, in which the length-to-diameter ration - 1.0, and a cube. volume = 1000 cm^3 for all three shhapes, and the same casting alloy is used. a) determine the solidification times of each geometry b) based on the results of part (a), which geometric element would make the best riser? c) if the mold constant = 3.5 min/cm^2 in chvorinov's rule, compute the total solidification time for each casting.