Provides heat to flowing magma that forms convection cells.

a) seafloor spreading

b) subduction

c) the lithosphere

d) earths core ✔️

Earth's Core

Explanation:

Earth's core provides heat to magma in the mantle, causing it to flow towards the lithosphere. This magma eventually cools and flows back towards the core, forming a convection cell.

3.2x10^7

the chart show the masses and velocities of two colliding objects that stick together after a collision.

according to the law of conservation of momentum, the momentum of the object after the collision is  

answer

1,500

kg • m/s.