Answer:

Explanation:
given data:
flow Q = 9 m^{3}/s
velocity = 8 m/s
density of air = 1.18 kg/m^{3}
minimum power required to supplied to the fan is equal to the POWER POTENTIAL of the kinetic energy and it is given as

here
is mass flow rate and given as


Putting all value to get minimum power


Answer:
Net force of the object is zero.
Explanation:
When an object is going to the left at constant velocity, this means there is no acceleration. Hence, no force. Had there been force,acceleration had been inevitable. Therefore, we can say that when an object moves with a constant velocity and in same direction, the net force on the object is zero.
There are 12 blue marbles, because this can basically be modeled as 3/2 = 18/x, which can be solved by mutiplying 3 and 2 by 6