Will give brainlest to the right answer

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?

The sum of two numbers is 12 and their difference is 18 what are the two numbers

What is the the greatest common factor ?