7) The minimum cross-sectional area of an aluminium conductor used in a 'power' sub circuit should be :

8) If mechanical and fire safety are important factors, the wiring should be :

9) A stair case point is operated with :

10) Outlets above 15 A rating should be connected through a :

11) What is the maximum permissible wattage of all the appliances on a 16A - fuse branch-circuit ?