If sec theta = - √30 / 3, find cos theta.
if sin(-theta) = -0.97, find cos (π/2 - theta).

Which of the following is correct interpretation of the expression -4+13

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. what distance from city a is the point where the truck and the car will meet?

Me because i don't understand how to do it.: )