Answer:
a)

b)

c) Generally the most probable speed is 8m/s as it the most posses by particles being the average
Step-by-step explanation:
From the question we are told that:
Sample size N=15

Generally the equation for Average speed is mathematically given by

Therefore


b)
Generally the equation for RMS speed of the particle is mathematically given by




c
Generally the most probable speed is 8m/s as it the most posses by particles being the average