Answer:
Your answer is 2.
Explanation:
To calculate the mechanical advantage of a pulley you simply have to count the number of rope sections that support whatever object you are lifting (not counting the rope that is attached to the effort). For example, in a one pulley system the MA is 1. In a two pulley system the MA is 2.
C, it is absorbed by earths surface.
Biology is the study of life so a Biologist would study biology: the study of life and living things.