public static Pressure FromCmHg(double hpa)
 {
     Pressure p = new Pressure();
     p.CmHg = hpa;
     return p;
 }
 public static Pressure FromAtm(double hpa)
 {
     Pressure p = new Pressure();
     p.Atm = hpa;
     return p;
 }
 public static Pressure FromTorr(double hpa)
 {
     Pressure p = new Pressure();
     p.Torr = hpa;
     return p;
 }
 public static Pressure FromHPa(double hpa)
 {
     Pressure p = new Pressure();
     p.HPa = hpa;
     return p;
 }