Answer:
Volume of hemisphere


Explanation:
The formula for the volume of a hemisphere is 

Substitute the points and solve.
N.B. 
 has a value of either 3.14 or
 has a value of either 3.14 or 

You can insert 
 directly into your calculator
 directly into your calculator
You now have the volume of the hemisphere.
Density (given) is mass (what we are looking for) divided by volume (what we found in the first step)
Substitute the values.
Change subject.
Solve.
Have a nice day. :)