Summarize the process by which new sea floor forms at mid-ocean ridges.

As tectonic plates diverge, lava rises up and forms a mountain like a shape on the ocean floor.
The lava cools down thus forming/adding a new ocean floor.

As tectonic plates converge, the plates go upwards and create a mid-ocean ridge also known as a mountain-like shape.

At the divergent plate boundaries new oceanic lithosphere is formed in the gaps of magma coming up from the mantle. I hope this helps;)

The answer is b im not sure 

Joe ran 130 yards because 3 feet make 1 yard so using this ratio 390 feet make 130 yards.