Please help Im in class

Aman steps out of a plane at a height of 4,000m above the ground falls 2,000m very quickly and then opens his parachute and slowly falls the remaining 2000m to the ground what height above the ground would be the best choice for a reference point

The highest point on earth is the peak of mount everest if you climb to the top you would be approximately 29,035 feet above sea level at remembering that amount is 5280 feet percentage of the height of the mountain would you have to climb to reach a point 2 miles above sea level

Mr. brettler is hanging up a 5-foot tall rectangular welcome sign in the gym. he has drawn a sketch on a coordinate grid. he has the lower vertices of the sign at (9, –3) and (–6, –3). where would the upper vertices be on the grid?