Which expression is equivalent to (x Superscript 27 Baseline y) Superscript one-third?.

Sam claims that cos x =sin y if x and y are congruent angels. is sam correct ?

10 ! a train starts from grand city and travels toward belleville 388 miles away. at the same time, a train starts from belleville and runs at the rate of 47 miles per hour toward grand city. they pass each other 4 hours later. find the rate of the train from grand city.

Can someone tell me if this is perpendicular? !