Mass divided by volume measures?

Ialready know the answers to these questions and they are on the attachment. but i just need to know why that answer is the correct one. plz asap! this is for a report that i need to email by 10!

Diego conducted an experiment to find out what kind of ball bounces the highest when dropped from a five-foot platform. he used a golf ball, a tennis ball, and a soccer ball. he dropped each ball from the balcony once. diego recorded his observations after each drop. what can diego do to best improve the reliability of his results? a) drop each ball from the platform three more times b) record his observations in more than one unit c) write at least two scientific questions after the experiment is complete d) share his results with other people who have done similar experiments you for the !

Me plz he did not infringe upon the policy making powers that he felt the constitution gave congress. but the determination of foreign policy became preponderantly a presidential concern. when the french revolution led to a major war between france and england, washington refused to accept entirely the recommendations of either his secretary of state thomas jefferson, who was pro-french, or his secretary of the treasury alexander hamilton, who was pro-british. rather, he insisted upon a neutral course until the united states could grow stronger. which provides the best objective summary of this excerpt? president washington made a good choice when he decided not to accept the recommendations of his advisors and instead insisted that the united states stay neutral during the war between france and england as president, washington believed that the united states should remain neutral in foreign policy even though he had advisors who recommended that he take sides during the war between france and england. washington did not make policy decisions during his presidency because he did not want to interfere with the policy-making powers that the constitution gave congress. washington refused to accept entirely the recommendations of either his secretary of state thomas jefferson, who was pro-french, or his secretary of the treasury alexander hamilton, who was pro-britis