Okay. There is a simple formula to go with this where:
p = mv
P: Momentum.
M: Mass.
V: Velocity
Sub the numbers in and solve for M.
10.0 = m(1.5)
10.0/1.5 = m
6.67 kg = m
Therefore the mass of the ball is 6.67kg.
I think it is "A'' 'It moves along straight lines in air and changes direction when it enters water.
Answer:

Explanation:
The period of a physical pendulum is:



The length of the leg is approximately the height of the person:

The period is:


D subtract the atomic number from the atomic mass
N = A - Z