A: Observation
Explanation: Scientist had to measure the worm to get its actual size, therefore they observed the size of the worm
1) Plants cell have "Cell wall" and animal cells lack of it
2) Plant cells have "Chloroplasts" but animal cells lack of it
3) Plant cells have "Vacuole" but animal cells lack of it
Hope this helps!
The Rocky Mountains formed 80 million to 55 million years ago during the Laramide orogeny, in which a number of plates began sliding underneath the North American plate. ... Since then, further tectonic activity and erosion by glaciers have sculpted the Rockies into dramatic peaks and valleys.
Most of the present physiographic regions of the Great Plains are a result of erosion in the last five million years. Widespread uplift to the west and in the Black Hills caused rivers draining these highlands to erode the landscape once again and the Great Plains were carved up.
The part of Earth that supports life is called as the earth's Crust .
The hilum serves as the passageway for nerves and vessels
