Your answers are both evocative and active forces. Hope this helps.
A large deposit of sand and soil formed at the end of a river is a delta. When a river empties into the ocean, the current carrying smaller particles, such as soil and sand, slows down and eventually stops, causing these particles to be dropped off on the shore. This eventually leads to a triangular deposit, usually referred to as the mouth of the river.
Magnification = 40mm/ 40 micrometer = 10^3
Cells are the basic unit of life
