Calculate the average speed between seconds 1 and 4 PLS HELP ME

Which of the statements about waves is true? a. in longitudinal waves, particles move perpendicular to the direction the wave is traveling.b. both transverse and longitudinal waves can travel through water c. electromagnetic waves are a type of longitudinal waves.d. in a transverse wave, particles move parallel to the direction the wave is traveling.

An object moves from the position +34m to the position -15m in 15 seconds. what is it's total displacement? what is it's average velocity?

Use the right-hand rule for magnetic force to determine the charge on the moving particle. this is a charge.