Just imagine the -------- as a solid line. It means divide.
You'll have to ask one question at a time because there is way to much jumble for me to disect. This stuff is kinda hard to explain to others but I'll try to make it understandable.
To start, those equations are meant to figure out two numbers, Pressure Ratio and Corrected Air Flow(lbs/min). If you look at a turbo compressor map it is built on these two numbers throughout a graph plotted against boost pressure. So if you wanna run say 15psi and redline @ 7500rpm then you want a turbo that is effecient as possible throughout your engines rpm range. You'll need to look at a compressor map to get what I'm saying first.
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