# A Hint Question to Robo-space volley

I had posted a question Robo-space Volley probably a month ago but found that not many could solve it. This is a question but simpler one on the same principle. A volleyball can be molded as a non-stretchable but flexible spherical envelope of mass m=260g and radius R=20cm filled with air at excess pressure $\triangle P=13atm$ This is a hypothetical volleyball. The excess pressure remains unchanged with small deformations in the volleyball when it is hit or when it strikes some rigid surface. Mass of the air inside the volleyball can be neglected. Such a volleyball strikes the wall and bounces back without loosing speed let the speed of the volleyball be v=3m/s. How long will the volleyball remain in contact with the wall. If the time taken is x then find units digit of [1000x] where [.] represents GIF

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