If you simplify 5mn - 8mn + 13mn whats the answer?

Aubrey read 29 books and eli read 52 books what number is equal to the number of books aubrey read?

What is the equation of the line that is parallel to the line with the equation y= -3/4x +1 and passes through the point (12,-12)

Amountain climber starts a climb at an elevation of 453 feet above sea level at his first rest stop he has climbed 162 feet and by his second rest stop he has climbed another 207 feet its getting late in the day so the climber starts his way down if the climber desends 285 feet how much does he need to ascend or descend to return to the original starting point