4. What is the minimum maintained distance between knobs in an open wiring method? a 30 centimeters c. 40 centimeters b. 50 centimeters d. 60 centimeters 5. in which location does the use of open wiring method prohibited? a commercial garages choist ways b. theaters d. all of the above 6. What is the condition of the conductors in an open wiring method? a concealed c. shorted b. visible d. grounded 7. What material is used to fasten a split knob or solid knob into wooden surfaces? a nail c. either a orb b. screw d nether a norb 3​