Few questions from first time grower (Any help is appreciated)

Hey guys I've had a plant growing now for about 9 days since it broke ground. I just have a list of questions that I'm unsure about and couldn't find a straight forward answer to.

1.) How high above my 9 day old plant should I hang my 400W MH light
2.) The temp in my grow tent is a constant 81. Sometimes temperatures reach 84 MAX. Is this going to be a problem?
3.) When should I start feeding my plant some FF Grow big? and should I only use about 1/4 of the recommended dose for the first few feedings?

The plant I am growing is just for fun and to experiment on so I'm open to any other suggestions of what to do with it. I'm going to grow it for another week or so (Until my real seeds arrive) and then force it to flower. Here are some pics of the grow space and plant.

ur light shold stay abot 20-24 inches away from ur plant...the temp is good but u need to make sure it doesnt get any high than 84...wait until atleast 3 weks old before u feed her anything earlier will stunt its growth and stress it out

If my room gets into the 80's I can't sleep at night. The girls like pretty much the same temperatures as humans (without c02). Although if you are running CO2 those are optimal temps. Will you second that cowasaki? Good luck with your future grow!