I need help ASAP pls I need help!!

Find an equation of the line perpendicular to the graph.

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?

Iwill give ! if m∠a=59 and m∠3=81°, what is m∠b? m∠b= _[blank]_°