Because it has atomic no. = 1 (according to modern periidic table)
Unlike humans, termites are able to extract energy from wood because: they have some microorganisms living in their gut that are able to break down cellulose.
A gauge records the pressure over atmospheric pressure (0kpa on the gauge is actually the atmospheric pressure and a reading of 276kpa is 276kpa over atmospheric pressure). That means that means that to find absolute pressure you just add atmospheric pressure (around 1atm (101kpa)) to 286kpa to get 387kpa. I hope this helps.