[Q]: What is the missing first step of the following process: - The radiation is aborbed by the Earth - Some of the radiation goes back into space - Some is trapped by the atmosphere - If too much heat is trapped - Global warming occurs.
****
[A]: The sun gives off radiation

[Q]: What is the missing first step of the following process: - A muscle fiber gets a signal from its nerve - Proteins and chemicals release energy to either contract the muscle or relax it - When the muscles contracts the bones connected to he muscle are pulled closer together - When the muscle relaxes the bones move farther apart.
****
[A]: Muscles work by expanding and contracting

[Q]: What is the missing first step of the following process: - The sediment breaks down into small particles - Wind or water picks up the sediment - The sediment travels along the same route as the wind or water - The sediment is deposited at new locations by the wind or water - The sediment is picked up again by new wind or water - The sediment travels further - The sediment is deposited again in a new place.
****
[A]: Sediment settles in a place due to gravity

[Q]: What is the missing first step of the following process: - The fault lines grow over time - The rocks on each side of the fault lines rub against the rocks on the other side of the fault line - The rocks put pressure on each other - The rocks break from the pressure - The breaking of the rocks releases a lot of energy - The energy causes seismic waves - The seismic waves make the earth shake.
****
[A]:
Fault lines appear underground