Answer: 10
Step-by-step explanation:
"To compare two earthquakes in terms of shaking, you subtract one magnitude from the other and raise 10 to that power: 10^(M1-M2)." (from science.org).
So, comparing a magnitude 8 and 7 earthquake,
8-7=1.
the stronger earthquake shakes 10^1 or 10 times as hard as the milder one.