1. A ladder 7 m long is leaning against a wall. If the bottom of the ladder is pushed horizontally toward the wall at 1.5 m/sec, how fast is the top of the ladder sliding up the wall when the bottom is 2m from the wall? 2. A horizontal trough is 12m long and its ends are isosceles triangles with an altitude of 3m. and a base of 3 m. Water in being drained from the trough at a rate of 2 m/min. How fast is the water level lowering when the water is I m deep?