How are scientists able to measure the age of earth?

By using relative dating! Scientists can find the age of a rock by using the law of superposition, which finds the relative age of a rock. The relative age of something is an estimate of how old something is. For example, "This rock looks to be around 1,000 years old!" At the end, you can make connections and eventually find a precise estimate to how old the Earth is.

Explanation:

I hope this helps! (This is in my own words, by the way) :>

conduction, convection, radiation

one person pulls 90n one way and the other has 100n pulling the other way.

so the net force = 90 - 100 = -10n,

or the ans can be 10n if the picture shows -90n and 100n instead.