Noah and kate are shopping for new guitar strings in a music store. noah buys 2 packs of strings. kate buys 2 packs of strings and a music book. the book costs $16. their total cost is $72. how much is one pack of strings? show your work and explain your reasoning in the space provided below.

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