Answer:
The time required by the man to get out of the way is 0.6 s.
Step-by-step explanation:
height of building, H = 53.4 m
height of block, h = 19.4 m
height of man, h' = 2 m
Let the velocity of the block at 19.4 m is v.
use third equation of motion
Now let the time is t.
Use second equation of motion
Time cannot be negative so time t = 0.6 s.