Needs clarification

sorry for bugging you but i need to ask

if i have a a fire element on one of my gear and shock on the other, when i do element crit do i have blistering and high voltage at the same time?

do i need to put that on a certain equipment?

in PVP , does skill points marked down or it wont be affected? unlike talents for example

an one last thing ,

reactor makes orb cast arc.thus arc < mythic skill > still be a proc?

thank you in advance