Find the measure of arc LN.*

Me. i can't figure out this question. give an explanation too. .

You have 138.72 in your saving account u take out 45.23 and 18.00 you deposit 75.85 into your account

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