The second one is A, amount of time
The answer is True. I’m pretty sure it’s right, if not my bad but try and see.
The main crop would be corn because it's mostly warm there all year round!
The correct answer is D. ocean floor mapping and earthquake tracking
Tracking earthquakes is helpful because it shows where it came from and what caused it, as well as how it affected the environment, while ocean floor mapping is useful because it shows how the bottom of the sea changed over time which happens due to tectonic activity.