I’m making a new skateboard trick called the rehearse 360 the name still needs work but how much seed and air would I need and when you get it you can help with the name

Why does lightning travel from clouds to the ground?

Acid precipitation chemically weathering a 5.0-kg limestone rock . which coukd be the result ?

Arailroad car collides with and sticks to an identical railroad car that is initially at rest. after the collision, the total kinetic energy of the two cars is a) the same as before. b) half as much as before. c) one third as much as before. d) one fourth as much as before. e) twice as much as before.