What should be a concern as a weldment becomes larger as more parts are added? That it is well supported so it does not fall. That it does not get too tall and the top cannot be reached by using a ladder. That you will have to stand on part of the weldment to reach the other parts to weld them. It may be too large to see over.

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?