Which combinations form compounds? How do you know?

What feature of cell theory is best demonstrated in the image

Atypical human cell is approximately 12.00 μm in diameter and enclosed by a membrane that is 5.000 nm thick. (a) what is the volume of the cell including the membrane? (b) what is the volume of the cell membrane? (c) what percent of the total volume does its membrane occupy? to simplify the calculations, model the cell as a sphere. enter your answers using four significant figures.

Which set of terms best describes a community of miners who live out in the countryside of west virginia and use specialized geographical equipment to analyze the composition of rocks