Historic time capsule found at Washington Monument. Before you go, we thought you'd like these... BALTIMORE (WBAL) -A piece of history has been discovered in Baltimore. The original cornerstone of the Washington Monument in Baltimore, thought to be long lost, was discovered last week while crews dug for a sewage tank.
We divide our energy use among four economic sectors: residential, commercial, transportation, and industrial. Heating and cooling our homes, lighting office buildings, driving cars and moving freight, and manufacturing the products we rely on in our daily lives are all functions that require energy.
Some organisms, called autotrophs, can produce their own energy using sunlight through the process of photosynthesis. Others, like humans, need to eat food in order to produce energy. However, that is not the type of energy cells use to function. Instead, they use a molecule called adenosine triphosphate (ATP) to keep themselves going.