Which structure is found in plant cell but not in an animal cell ?
a) cell wall
b) cell membrane
c) cytoplasm
d) nucleus

Agas can holds 2.0 gal of gasoline. what is this quantity in cubic centimeters?

Which of the following did jj thompson discover about atoms? a)an atom has an internal structure. b) atoms are tiny indivisible particles. c)electrons orbit the nucleus of an atom. d) the nucleus of an atom contains protons and neutrons.

What happens to isotopes that are unstable?