Why did leeuwenhoek have an advantage over other scientists studying small items?

Which equation is used to calculate the magnetic force on a charge moving in a magnetic field

Acell in the human nervous system whose primary function is to form myelin and the blood-brain barrier, respond to injury, remove debris, and enhance learning and memory is called a(n) cell.

Which of the following is the earliest era of earth's geologic time scale? cenozoic mesozoic precambrian paleozoic