Hint 1.2
We know that the force transferred to you is the change in the water's momentum per unit time. The change of momentum is the initial momentum minus the final momentum (zero). The change in time is 1.00 second. The initial momentum of the water is the mass of the water times its velocity. We know the mass of the water because we know 3.00 m3 of water leaves the pipe in each second. We know the speed of the water in the pipe can be determined from the flow rate and the cross-sectional area of the pipe. We assume the water hits you with this speed. - That's a number of pieces to put together, but think through the details and it's not too hard.