Help out please?

In the 1800s, one of the statements in john dalton's atomic theory was that atoms are indivisible. later experimental evidence led to the discovery of subatomic particles such as neutrons, electrons, and protons. what happened to the indivisible atom part of dalton's atomic theory, and why?

Asolution contains 225 g of sodium chloride, nacl, dissolved in enough water to make a 0.25 l of solution. what is the molarity of the solution?

Amedication is given at a dosage of 3.000 mg of medication per kg of body weight. if 0.1500 g of medication is given, then what was the patient's weight in pounds (lbs)? there are 453.59g in 1 lb.