Abod test is to be run on a sample of wastewater that has a five-day bod of 230 mg/l. if the initial do of a mix of distilled water and wastewater is 8.0 mg/l, and the test requires a decrease in do of at least 2.0 mg/l with at least 2.0 mg/l of do remaining at the end of the five days, what range of dilution factors (p) would produce acceptable results? in 300 ml bottles, what range of wastewater volumes could be used?

Apump is used to circulate hot water in a home heating system. water enters the well-insulated pump operating at steady state at a rate of 0.42 gal/min. the inlet pressure and temperature are 14.7 lbf/in.2, and 180°f, respectively; at the exit the pressure is 60 lbf/in.2 the pump requires 1/15 hp of power input. water can be modeled as an incompressible substance with constant density of 60.58 lb/ft3 and constant specific heat of 1 btu/lb or. neglecting kinetic and potential energy effects, determine the temperature change, in °r, as the water flows through the pump.

Assuming compressible flow of air and that the measurements are done at flagstaff a pitot static tube that gives the difference of total and static pressure measures 0.35 m of mercury. what is the velocity of air? assume the temperature to be 300k. (submit your excel or matlab calculation sheet)

Aquick transition of the operating speed of a shaft from its critical speed will whirl amplitude. (a) increase (b) limit (c) not affect (d) zero