What is energy and what is the formula of energy

Individuals who live below the poverty line get seriously ill more often than those who do not what could be the hidden variable in this situation?

The built in flash in a compact camera is usally capable of giving correct exsposure for distance up to how many meters?

Ascientist notices that an oil slick floating on water when viewed from above has many different colors reflecting off the surface, making it look rainbow-like (an effect known as iridescence). she aims a spectrometer at a particular spot and measures the wavelength to be 750 nm (in air). the index of refraction of water is 1.3