As there are multiple answers going with trial and error seems good in this case.
A
5.00 + 5.00 + 5.00 + 5.00 = 20.00
3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 = 31.5
20.00 + 31.5 = 51.5
B
5.00 + 5.00 + 5.00 + 5.00 = 20.00
3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 = 35.00
20.00 + 35.00 = 55.00
C
5.00 + 5.00 + 5.00 = 15.00
3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 + 3.50 = 31.5
15.00 + 31.5 =46.5
Knowing that for the first one all A,B, and C were wrong we can determine that D is the answer. But wait if I made one mistake and didn't understand if $156.5 is equivalent to $156.50 that would mean A is correct.
Always recheck your answers and good luck,
Jon
It’s simple. The volume of a sphere is V=4/3πr^3.. so you will convert the mm to m okay?? 10mm=1cm .. so do your conversion from here then when you get the radius then you will substitute it into the volume where r is the radius.. so for the first one l changed mm to cm so.. radius is 4cm then l substitute it into the formula so l got 270 after rounding it to the nearest tenth.. pi=22/7 bear in mind. So do the same for the other one
825
You just multiply 1000 × 0.825 = 825 students