Cos inverse (cos 2pie by 3) + Sin inverse (Sin 2pie by 3) = ?​

Easy points boii. read it. ya. fresh

Aiden drives to school and back each day. the school is 16 miles from his home. he averages 40 miles per hour on his way to school. if his trip takes 1 hour, at approximately what speed does aiden drive home?

Factor the monomial completely 42a3b3