Given an idealephericaly radiating noise source, what would the sound level reduction be if the distance between the and receiver is decreased by a decade assuming the far field? a)-3 db b)- 10 db c)- 6 db d)- 20 db e)- none of the above

Estimate the change in specific internal energy au and specific enthalpy h from inlet to outlet for ethylene glycol (a liquid) flowing through each of the following devices: (a) a heat exchanger where the glycol temperature increases from 20 °c to 80 °c; (b) a pump operating at about 25 °c and increasing the glycol pressure from 100 kpa to 8 mpa.