I'm looking for some help on these problems:

1. A ladder 10 ft long rests against a vertical wall. Let theta be the angle between the top of the ladder and the wall and let x be the distance from the bottom of the ladder to the wall. If the bottom of the ladder slides away from the wall, how fast does x change with respect to theta when theta = pi/3

2. lim t -> 0 tan6t / sin 2t

3. lim x -> 0 sin(cosx) / secx

Thanks a lot!