Answer:
28043.3 
Step-by-step explanation:
Formula for volume of a hemisphere can be termed as:

where
is the radius of hemisphere
Please refer to the figure attached for the sample figure of a hemisphere.
We are given here, diameter of hemisphere = 47.5 m
Relation between diameter and radius is given as :

where,
is the radius and
is the diameter.
So, 
Volume is:

Hence, volume of given hemisphere is 28043.3
.