which statements are true? select all that apply.
a. an atom is the smallest complete part of an element.
b. an element is a pure substance made of one kind of atom.
c. the nucleus is the tiny center of an atom, and it contains protons and neutrons.
d. isotopes are atoms of the same element that contain the same number of neutrons but different numbers of protons.

A, B, and C

Explanation:

I just took a quiz with this question and these were the correct answers. :)

ń, wǒ shuō yīngyǔ, dàn wǒ huì shuō qítā yǔyán, rú xībānyá yǔ fǎyǔ yìdàlì yǔ hé pǔtōnghuà, suǒyǐ bùyào pànduàn, dànshì

for e2020. the answer would be some directions from the mountain range so we can find mt. whitney. to locate which direction is north, you should use a   compass. this would not only find mt. whitney, but also becuase of this long paragraph you would get points because it's not like anyone actually reads your work becuase once they read the first sentence it sounds dumb enough to not read becuase i'm not good at answering this but the answer is compass for your benefit.

for e2020 ; -;