An observer whose eye level is 1.5 m above the ground sights the top of thevertical wall of Washington Cliff at an angle of elevation of 799. If the observer is 211m from the base of the wall, find the height of the cliff to the nearest tenth of a meter.

∆red ≅ ∆ by rule will give brainiest if possible

The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 0 a. at what time does the particle reverse direction? b. when is the displacement positive? (round one decimal place and answer in interval notation) c. when is the displacement negative? (round one decimal place and answer in interval notation) d. when is the particle’s acceleration positive? (round one decimal place and answer in interval notation) e. when is the particle’s acceleration negative? (round one decimal place and answer in interval notation)

Typically a point in a three dimensional cartesian coordinate system is represented by which of the following answers in the picture !