Which is true for a shotgun but not for a rifle or a handgun?

the projectiles are pellets.

a shotgun has lands and grooves in the barrel.

a shotgun shell does not use a primer.

shotguns do not have firing pins.

What is relative velocity? in which condition is relative velocity known by adding the velocity of the first body and that of the second body

Describe the function of the endomembrane system? what organelles are involved?

Afisherman notices that his boat is moving up and down periodically without any horizontal motion, owing to waves on the surface of the water. it takes a time of 2.20 s for the boat to travel from its highest point to its lowest, a total distance of 0.670 m . the fisherman sees that the wave crests are spaced a horizontal distance of 5.80 m apart. (a) how much is the wavelength? (b) find the period of the wave. (c) how fast are the waves traveling? (d) what is the amplitude a of each wave?