To save a woman from a burning building, the firemen placed a 10-meter ladder against the window. The foot of the ladder was 6 meters from thewall. Approximately how high was the window?

How do i start to solve? would appreciate a walk-thru! a bird sitting 16ft above the ground in an apple tree dislodges an apple. after how many seconds does the apple land on the ground? (assuming that no branches will interfere with it's fall)