12. In a test of the centrifugal pump shown in the Figure 1 the following data are taken: p1=100mmHg (vacuum) and p2=500mmHg (gage). The pipe diameters are D1=12cm and D2=5cm. The flow rate is =0.01m3/s of light oil (SG=0.91). Estimate (a) the head developed, in meters; and (b) the input power required at 75 percentage efficiency. Figure Q12 Calculate the head: a) 11,2m b) 12m c) 10,9m d) 10m e) 9,9m [2 marks] 13. Calculate the power: a) 2000,2W b) 2551,8W c) 2332,7W d) 2400W e) 2409W