" 30% " means " 0.30 "
30% ÷ 75 means (0.30 / 75) = <em>0.004</em>
Unf there's no diagram. but this looks like a sort of celsius to fahrenheit temp scale conversion sort of problem.
Answer:
Velocity from second channel will be 1.6875 m/sec
Explanation:
We have given width of the channel , that is diameter of the channel 1
= 12 m
So radius 
Speed through the channel 1 
Width , that is diameter of the channel 2 
So 
From continuity equation



So velocity from smaller channel will be 1.6875 m /sec
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