If you ate a burger, you would probably only get about of the original energy from the sun

Which best describes the nucleus of an atom a. it is where all of the particle s of the atom are located b. it is the negatively charged part of the atom c. it is where the electrons and the protons are located d. it is the part of the atom with the greatest mass

What are the student's observations and inferences before he starts his investigation?

Which kind of worm has a closed circulatory system? a planarian b fluke c pinworm d an earthworm