The ball with a mass of 1.5 kilograms is tied to the end of

Explanation:

It is given that,

Mass of the ball, m = 1.5 kg

The ball is pulled to a height of 0.5 meters and then released.

The potential energy at point B is given by :

To find the velocity at point A, it is required to use the conservation of energy as :

v = 3.13 m/s

Hence, this is the required solution.

6

Step-by-step explanation:

This is a case of combination since the order does not matter, it only matters that there must be a marble in each one inside, therefore we must apply its formula.

xCn = n! / x! * (n - x)!

n, in this case it would be 4 because we must subtract 2 from the total 6, since there must already be one inside in each display case.

x = 2, since it is the number of showcases.

Replacing:

 2C4 = 4! / 2! * (4 - 2)! = 6

Which means that you can in six different ways.