What is the pressure of the gas in this mercury manometer if h = 59 mm and atmospheric pressure is 771 mmhg?

First we must remember that the unit  for pressure is usually written in SI units, and we have to convert all the given parameters to metric units. Given are height h=59mm convert this to "meter" just simply divide 59 to 1000. Next is Pressure equal to P=771mmhg(at 0 degrees Celsius), convert this to "Pascal" or Newton per square meter (N/m2). The standard atmospheric pressure is equivalent to 101,325Pa. This represents the force of pressure of the atmosphere pressing on our body. The density of air is equivalent to 1.225kg/m3. Now, write first all the given, h=( ? ) P2=101,325Pa, Density of Air Da=1.225kg/m3. The normal pull of gravity g = 9.8m/s2. Unknown Pressure is P1=? . Then follow this formula  (P1 = P2 + Dgh).