What are the advantages and disadvantages of the practice of direct democracy (initiatives, referendum, etc.) in state governments?

Which is not a characteristic of a heat pump? a. it is used in air conditioners. b. it uses a refrigerant. c. it requires no work. d. it reverses the normal flow of thermal energy.

What is the measure of a change in an objects velocity?

Why can blue light and yellow light combine to produce white light? question 17 options: they are both primary colors of light. they absorb each other's wavelengths. because blue, yellow, and white are primary colors. they are complementary colors of light.