What type of energy is represented by a battery

Which type of reaction always has an element and a compound as reactants

The graph above shows how the price of cell phones varies with the demand quantity. the equilibrium price for cell phones is where both supply and demand quantities equal $100, 5,000 5,000, $100

Ahydrogen atom has 1 electron. how many bonds can hydrogen form? a) 1 b) 2 c) 3 d) 4 e) 5