***see attached pic***
Some helpful tips:
The nucleus is always going to be the big, spherical shape.
The ER is always going to be a weird, folded looking structure attached to the nucleus (rough = has ribosomes on it which are usually represented by little dots, smooth = has no ribosomes on it aka no dots)
The GA looks like the ER but it is not going to be attached to the nucleus like the ER is.
The mitochondria is always going to be pill-shaped and have weird folds inside of it.
Clues such as fossils such as bones, footprints, tar, etc, preserved underground helped inform scientists. You can also count how old a tree is when you cut it open and there are some alive for thousands of years so that is a possible way.
The answer to this question my fellow advisory lol is True
A zinc, Zn, atom contains 30 protons inside the nucleus and 30 electrons outside the nucleus. hope this helped :)
Photosynthesis is performed in the chloroplasts.