5. How many molecules are in 0.550 moles of N2O5?

Plz mark brainliest 30 points1) find the momentum of a 12 kg snowball that is rolling with a velocity of 9 m/s.2) an 8 ball with a mass of .5 kg is sitting at rest. it is hit by the cue ball (1 kg) traveling at 2.5 m/s. if the cue ball is at rest after the collision, how fast is the 8 ball traveling after the collision? 3) two football players are running toward each other. if the offensive player is 75 kg and is running 8 m/s, how fast must the 60 kg defensive player run in order for the two players to hit and stop?

Can someone me with 3 and 4 plz. this is for masteries test.

Using the first volume and temperature reading on the table as v1 and t1, solve for the unknown values in the table below. remember to use the rules of significant figures when entering your numeric response.