If you are a meat eater, you are less likely to suffer from zinc deficiency as meats are one of the best foods rich in zinc. The meats that have the highest concentration of zinc include beef, lamb, pork, chicken and turkey. A 100 gram serving of cooked lean beef contains 12.3 mg or 82% DV of zinc.
Endothermic reactions absorb energy from the surroundings, while exothermic reactions release energy to the surroundings. Fuels release energy when they burn. The energy output of a fuel can be measured by calorimetry using a known mass of water.
An exothermic reaction releases heat into the surroundings, and an endothermic reaction absorbs heat from the surroundings. Frying an egg is an example of an endothermic process because the egg solidifies as it absorbs heat from the frying pan. A common example of an exothermic reaction is combustion in the form of a bonfire -- anyone near the flames can readily determine that the fire is releasing heat into the surroundings.