Since you are giving no information whatsoever, the formula could be:
S = (1/2)g.t², where s is the distance, 9 =9.8 m/s² and t = time
S = (1/2).(9.8)(2.2)² ans S= 23.7 meters
X= shift tan 0.3
x=16.6992≈17
I think the best figure for a cereal box would be a cylinder. There are no corners on a cylinder where it is hard to fit round pieces of cereal into. The formula for the surface area of the cylinder is 2*pi*r*h+2*pi*r^2. The formula for the volume of the cylinder is pi*r^2*h. (Then I would add some more info supporting why you think a cylinder would make a good box.)
The diameter is equal to the radius multiplied by 2.