The nutritional recommended daily allowance (rda) of calcium is 1,300 mg for a 9-18-year-old. How many grams is this? How many atoms of calcium is this?

Which characteristics can be used to differentiate star systems? check all that apply.

The famous scientist galileo galilei did several experiments with sloping planes, which he rolled metal balls down so that he could study motion. by changing the slope, he could study how the speed at which the ball rolled was affected. what was the independent variable in galileo's experiment? a. the speed of the ball b. the slope of the plane c. whether the ball moved d. what the ball was made of

Identify the correct mole ratio for each substance. sodium chloride (nacl) na: cl = 1: ammonium nitrate (nhno) h: o = 4: