A fitness center bought a new exercise machine called the mountain climber. They decided to keep track of how many people used the machine over a 3- hour period. Complete the given probability...

A fitness  center bought a new exercise machine called the mountain climber. They decided to keep track of how many people used the machine over a 3- hour period. Complete the given probability distribution and find the mean, variance, and standard deviation for the probability distribution.  X is the number of people who used the machine.

X                 0            1         2            3           4

P(X)           0.1        0.2      0.4                      0.1