What would the altimeter read if Janelle were at sea level? What do the positive readings on the altimeter represent? What do the negative readings on the altimeter represent? pls awnser with a good awnser

If the ratio of sum of the first m and n terms of an ap is m2 : n2 , show that the ratio of its mth and nth terms is (2m − 1) : (2n − 1).

Boris needs to buy plastic spoons. brand a has a box 42 spoons for $2.37. brand b has a box of 72 spoons for $3.57. find the unit price for each brand. then state which brand is the better buy based on the unit price. round your answer to the nearest cent.

Use the elimination method to solve the systems of equations. choose the correct ordered pair. 7x+4y=39