What are the two rivers in mesopotamia? how did they to create a civilizationin this reigon

What refers to the division of power among the three branches of government

The civil rights act that passed in 1964

Ascientist performs an experiment where she measures the mass of a piece of metal, pours acid onto the metal, washes the metal, and then re-measures the mass of the metal. the scientist repeats the experiment several times, each time increasing the amount of acid used. the dependent variable in the experiment is the: initial mass of the metal final mass of the metal amount of acid used washing the metal