Options please i think its John Dalton
A coal because coal is one of the most natural items on the list
An extensive property is a property that deals with the amount of a substance. An extensive property of marker ink would be the volume of the ink in the pen.
An intensive property is a property about the type of substance you're looking at. So, an intensive property of marker ink would be the color of the ink.
It is OH- (hydroxide ion)
I would personally convert the 12 mg to g so I could see what I was working with. So 12 mg to grams is 0.012 g...
so 1 tablet is 0.012g. the patient needs 0.024 g.
so 0.024g/0.012g = 2 tablets or 0.012g X 2 is 0.024 g
hope this helps :)