Please help me answer this

You are on a cycling trip around europe with friends. you check the weather forecast for the first week. these are the temperatures for the week. sun mon tues wed thurs fri sat 16°c 20°c 24°c 28°c 28°c 23°c 15°c what is the mean temperature forecast for the week?

When y’all answer can y’all explain too !

What is the 9th term in the geometric sequence described by this explicit formula? an=-6. (2)(n-1) apex