the parking lots elevation is 400.14 feet. the buildings fin floor elevation is 401'-6 1/4. the path from the parking lot to the building is 30' long. if the grade is greater than 5%, then a hand rail will be required. will we have to install a handrail?

Ahe-xe mixture containing a 0.75 mole fraction of helium is used for cooling electronics in an avionics application. at a temperature of 300 k and atmospheric pressure, calculate the mass fraction of helium and the mass density, molar concentration and molecular weight of the mixture. if the cooling capacity is 10 l, what is the mass of the coolant?