Lagoons used for purification of polluted water________?

Alum is commercially produced from________?

Rate of an autocatalytic chemical reaction is a function of ________?

Steel is welded using the ________ flame?

For a cylindrical shell, (subject to the thickness of uppermost course being more than the minimum for dia of the tank in question), the thickness of the courses of shell________?

Cox chart is useful in the design of________?