It a question is testable and can provide an answer based on empirical observations and reasonable logic, it can be answered with science

How many moles are equivalent to 55.5g of nano3

The number at the end of an isotope’s name is the number.

A40 kilogram skier starts at the top of a 12 meter high slope. at the bottom, she is travelling 10 meters per second. how much energy does she lose to friction