Make a dichotomous key that could be used to classify mollusks and annelids into the correct class.

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.

the answer is :

the atomic number of magnesium is 12. its nucleus must contain 12 protons and no electrons. the atomic number of an atom is determined by the number of protons.

magnesium is an electrolyte injection commonly used to treat low magnesium levels in your blood. it is also used to prevent or control seizures in women with preeclampsia or eclampsia.

"it built up in the atmosphere"

i think thats it, idk, i tried looking for this exact q& a for grad. and idk if i got this question right or sorry if im wrong