I need help with #5 please

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 difference between two numbers is one. three times the larger number minus two times the smaller number is 9. what are the two numbers

Over the last 4 seconds, a snail has traveled 4/9 of an inch. if the snail traveled the same distance each second, how far did it travel each second?