PLease help. Jim wants to react hydrogen and oxygen to get 36 grams of water.

If he starts with 4 grams of Hydrogen (H), then how many grams of Oxygen does he need for the reaction? grams

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