When jacob bats a baseball with a net force of 4.719n , it accelerates 33 m/s squared, what it the mass of the baseball

Force is given by m*a

thus

4.719/33 = 0.143 kg

that's 143 grams

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me