1 Is advantage because with out is. you couldn't carry the piano at all.
2 Efficiency because it is going against you.
Their combined momentum after they meet is 0 .
Explanation:to find the area you must first find the radius given you have the diameter you cut the diameter in half giving you 40 then you follow the formula “A= (pie)r (squared) leaving you with
answer:5024
It has 99 electrons because an element has the same number of protons and electrons