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NPSHA = Hatm +Hz - Hvp - Hf Hatm = Hvp so they cancel out. 12-3.5 = 8.5 feet  Answer (C) What I originally did was not use absolute pressures and I also ignored vapor pressure.  Now I know better.

(B)

Which Companion problem? MERM Practice Problem 25-6?

At least you were smart enough to not use your real name on these boards when you make a mistake.  Unlike myself.

Your are using the wrong enthalpies to calculate the shaft power.  You use the h2 real - h2 ideal.  You need h1 - h2real.

I bought a lunch in a cooler and left it in my car.

Depends on how much stuff you have to carry and how far you have to carry it....   

If I were you, I would have all the combustion problems figured out before the exam.  Like all the molecular weights for each component that you see, co, co2, h20, ect.....  I would pre-figure out all the fuels methane, propane, and know how to calculate the moles for exhaust...

(B)

See equation 18.41 in MERM....  

You forgot to divide by the 70%...  To get the water flow required. I came up with (B) for the answer.   I did my calculations differently than yours.  I have quick equations on my Psych chart here...  

The problem states...    "The inlet suction gauge indicates 6 in (150mm) of mercury below atmospheric."    If you remove the pressure gauge, what does it read in open air?  It reads 0 psig.  Gauges only read the pressures above or below atmospheric pressure.  If the pressure is below...

The solution worked the problem in absolute pressures.  You do not need to work the problem in absolute.  You are messing up the gauge pressure, though.

What is the gauge pressure of 14.7 psia (atmospheric condition @ sea level)?  0 psig... Pabsolute = Patmosphere + Pgauge

Gauge Pressure would be -2.95 psi.  Absolute Pressure would be 14.7 - 2.95 = 11.75 psia You can just use gauge pressures for P1 or P2...  Or you can use absolute pressures for P1 or P2.  Just don't mix gauge and absolute.

Refrigeration Capacity + Power Input = Condenser Heat Of Rejection.  39.1 MBH + 3.22kW x 3412 btu/hr/kW / 1000 btu/hr/MBH = 50.1 MBH (C)

Just remember to relax and work through the problems methodically.  Do not rush through the exam and certainly do not panic.

I did it...  I just didn't want to spoil it for anyone else. (D)

When I ran out of exam type questions, I started doing the PPI problems book.  They are a little more difficult but I believe the more difficult problems help develop a better understanding on how to solve the problems. I started feeling confident about the exam and then that shifted to a false...

Sure!!!  Where was this 2 years ago when I was studying for my exam????   BUT NO.....   Mike had to use the Black and White one and had to blow it up to 11X17 so his eyes wouldn't cross...