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Answer:
Explanation:
Given
average speed of Phelps 
total distance 
he swims first 100 m at an average speed if 
so time taken is 
suppose
is the time taken to swim remaining half
average velocity is 



so velocity in the second half is

Answer:
d = 380 feet
Explanation:
Height of man = perpendicular= 130 feet
Angle of depression = ∅ = 70 °
distance to bus stop from man = hypotenuse = d = 130 sec∅
As sec ∅ = 1 / cos∅
so d = 130 sec∅ or d = 130 / cos∅
d = 130 / cos(70°)
d = 380 feet