PLEASE answer im lost

Lizette is training for a marathon. at 7: 00 she left her house and ran until 8: 30, then she walked until 11: 30. she covered a total distance of 18 miles. her running speed was six miles per hour faster than her walking speed. find her running and walking speeds in miles per hour.

What is the 17th term in the arithmetic sequence in which a6 is 101 and a9 is 83

Which expression is equal to (f+g)(x)?