Which two particles are always tound in equal numbers in neutral atoms A. Protons and electrons B. Electrons and neutrons C. Neutrons and ions D. Protons and neutrons

This image is an example of a(n) a) atom. b) compound. c) mixture. d) molecule.

Avariable that is not being directly tested during an experiment should be

An animal cell loses the ability to convert energy stored in food to energy that the cell can use. which of the cell's organelles has stopped working? a. the mitochondria b. the nucleus c. the vacuoles d. the endoplasmic reticulum