A bathball with the volume 3,0dm^3 is floating on water and has 6,0% of it's volume down in the water.

a) Count the bathball's mass , Easy : 0,06*3,0= 1,8hg = 0,18 kg

Now comes the real problem

b) how much power do you need to use to force the whole bathball down under water?

Well for this I though i'd use p*v*g /p (where p is water density)

Water density 1,0 * 10^3 = 1000*0,3m^3*9,82 = 2946 / 1000 = 2,946 N

Which totaly wrong it should be 28 N how do I solve this?