1.√2.√3.× (the symbol of resistance is r, and u is the symbol of voltage).

4. √ 5 .× (1.5mm2)

6.√7.√8.√9.× (carbon and mercury are not conductors) 10. √.

1 1.× (special insulating tape for power is required) 12. √.

13.×(22:00 to 8:00 the next day is the period of low power consumption)

14.× (Energy-saving fluorescent lamps, of course. Only by saving electricity can the utilization rate of electricity be high. )

15.√

Is it detailed enough, O(∩_∩)O~