With what acceleration does a steel ball move into the sea, with what resultant force does it hit the seabed, and how long does its motion take? The depth of the sea is $m=100 \mathrm{~m}$. The diameter of the ball is $d=0.20 \mathrm{~m}$. The specific gravity of the steel ball is $\sigma=7.23$; the specific gravity of seawater is $\sigma_{1}=1.05$.