Two pieces of evidence for plate tectonics?

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

Two 2.0-cm-diameter disks face each other, 1.0 mm apart. they are charged to ±10 nc. what is the electric field strength between the disks? a proton is shot from the negative disk toward the positive disk. what launch speed must the proton have to just barely reach the positive disk?

Examine the drawing of a molecule. each ring represents an atom of nitrogen (n). what’s the chemical formula of this substance?