Which of the following best explains why tangent StartFraction 5 pi Over 6 EndFraction not-equals tangent StartFraction 5 pi Over 3 EndFraction?

Simplify 6sin θsec θ. choices a) 6 tan θ b) 6 cos θ c) 6 cot θ d) 6

Expresa commuter train leaves downtown sation and travels at a average speed of 55 miles per hour towards the north side sation, which is 50miles away. thirty minutes later, express commuter train #7 leaves north side and travels at a average speed of 35miles per hour towards downtown sation. at the moment the two trains pass each other, how far(in miles) is train #12 from the downtown sation and how long(in minutes) has the #12 train been traveling

Ineed to know the answer to this algebra question.