Answer:
(a) 3.44 x 10^-3 m^3/s 
(b) 8.4 m/s
Explanation:
area of water line, A = 5.29 x 10^-3 m 
number of holes, N = 15 
Speed of water in line, V = 0.651 m/s 
(a) Volume flow rate is given by 
V = area of water line x speed of water in water line 
V = 5.29 x 10^-3 x 0.651 = 3.44 x 10^-3 m^3/s 
(b) area of one hole, a = 4.13 x 10^-4 m 
Let v be the velocity of water in each hole
According to the equation of continuity 
A x V = a x v
5.29 x 10^-3 x 0.651 = 4.1 x 10^-4 x v 
v = 8.4 m/s