What is seven over twenty one take away one over twenty one in its simplest form

Ammonia molecules have three hydrogen atoms and one nitrogen atom.how many of each atom arein five molecules of ammonia

The ph level of a blueberry is 3.1 what is the hydrogen-ion concentration [h+] for the blueberry

Non-euclidean geometry was discovered when, in seeking cleaner alternatives to the fifth postulate, it was found that the negation could also be true a. true b.false