heres a pic of what were looking at:

http://img183.imageshack.us/img183/8004/untitledqa0.jpg
A hiker needs to cross a sandy area in order to get from point A to a camp site at point B. He can do so by crossing the sand perpendicular to the trail and then walking along the trail, or by crossing the sand in an anle theta up to the trail, and then walking along the trail. The hiker walks 3.5 km/h in the san and 5 km/h on the trail. Determine the time it will take him to reach the camp site for theta = 0, 10, 20, 30, 40, 50 and 60 degrees.

not sure how to do this one. help is needed please.