What force is required to submerge the ball in water

A tennis ball has a density of 0.084 g/cc and a diameter of 3.8 cm. What force is required to
submerge the ball in water?

density = 0.084 g/cc = 84 kg /m^3
diameter of 3.8 cm = 0.038 m
floatation
= weight of water displaced
= [4 pi (0.019)^3 / 3 ] * 1000 * 9.81 N
weight of tennis ball
= [4 pi (0.019)^3 / 3 ] * 84 * 9.81 N
force is required to submerge the ball in water
= [4 pi (0.019)^3 / 3 ] * 1000 * 9.81 - [4 pi (0.019)^3 / 3 ] * 84 * 9.81
= 0.253N
answer

radius = 0.019m
volume of ball = [4 pi radius ^3 ] / 3

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Weight of ball (πd²/4) ρg
Weight of water displaced (πd²/4) 10^3g
For submerging (πd²/4) ρg + F = (πd²/4) 10^3g
where F is the extra force needed

F = (πd²/4)*9.8 { 10^3- ρ}

F = (π 3.8e-2²/4) 9.8{ 10^3- 84 kg/m^3} = 10.2 N
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You need a force equal to the mass of the DISPLACED WATER in this example. Calculate the volume of the ball mass and multiply times its density. You need an equal force to PUSH it upwards.

A aircraft.