Household plants and such, not grass.
Get an onion bulb and place it in moist sand or vermiculite for about a week and you'll get easy to see roots. Or find some paper Narcissus bulbs and place them in water.
i have no idea what home oxygen is, but ANY additional amount of gaseous oxygen near a burning process will speed it up. faster burning means bigger and most importantly HOTTER flames, since more energy is set free in the same amount of time. the more oxygen the bigger the effect.
