A3 kg piece of putty that is moving with a velocity of 10 m/s collides and sticks to an 8 kg bowling ball that was at rest. what is their velocity as they roll away together

Ineed the answer to question 1 , i’m desperate

The seven sisters, seven stars located more than 400 light-years away in the taurus constellation can be seen here with venus and another constellation, orion. the seven stars stay grouped together but seem to move, like the planet venus. why do stars seem to move like planets in the night sky?

On a day when the barometer reads 75.23 cm, a reaction vessel holds 250 ml of ideal gas at 20 celsius. an oil manometer ( ρ= 810 kg/m^3) reads the pressure in the vessel to be 41 cm of oil and below atmospheric pressure. what volume will the gas occupy under s.t.p.?