Dos corredores A y B se muevenen promedio a 10,5m/s y 39km/h respectivamente. ¿Quién llega primero a una meta situada a 100m?​

If there was no gravity then their would be no downword force on the football to have it return the the grownd, and if there was no friction (mainly air friction) then there would be no opposing force the stop the ball from moving through the air allowing the ball to travle ∞.

2.77 x 10^-3 its for plato user 

So since the snail is moving at 3.6  miles per hour you multiply by 5280 to change it into feet per hour. so you get 36*528 ft per hour. since there are 3600 seconds in an hour, you divide 36*528 by 3600. so simplifying we get 528/100 which is 5.28 ft per second

The fuzzy edges of shadows are a result of  diffraction