A system gains 697 kJ of heat, resulting in a change in internal energy of the system equal to + 251 kJ How much work is done?

What type of electromagnetic waves does the human eye see as the colors red blue or green a visible light waves b radio waves c infrared waves d microwaves

What is the formula of the ionic compound composed of calcium cations and chloride anions

Afusion reaction takes place between carbon and another element. neutrons are released, and a different element is formed. the different element is a) lighter than helium.b)heavier than helium.c)the same weight as helium.d)dependent on the element that reacted with carbon.