1 and 3 are opposite angles so they have the same measure. 2 and 1 are adjacent angles on a linear plane. since a line is 180 degrees and we know that one of the angles on this plane is 62, that means that angle 2 must be 180 - 62 which 118 degrees
Length of train : 100 length of bridge : 400 distance covered by the train to cross the bridge : (100 + 400) = 500 time taken by the train to cross : 30
speed = distance / time speed = 500/30 speed = 16.67 meters per second <===
