Which one of the following is the base metal for the process 'hot dip coating' ?

34) In an aluminium etching treatment, if the solution having 2% nitric acid, 2% sulphuric acid and 0.5% hydrochloric acid, is used at 100 Degree Centigrade for 15 minutes, what type of finish can be obtained ?

35) Silver or copper finishes are generally used on lighting fittings, name plates etc. Which one of the following is the process for this ?

36) Which one of the following is the base metal for the sprayed metal process ?

37) Which of the following is a surface finishing operation?