When a chemical system is at equilibrium, the concentrations of the reactants are equal to:. 1. the concentrations of the products.
2. the concentrations of the reactants and products have reached constant values.
3. the forward and reverse reactions have stopped. the reaction quotient, , has reached a maximum.
4. the reaction quotient, , has reached a minimum.

If you explain it more through i will answer it : )

Firstly, the water in the dams hold gravitational potential energy as they are above ground level. the gravitational potential energy is then transferred to kinetic energy as it falls, spinning the turbinethe turbine then spins the generator, which is a large magnet surrounded by metal coils. by doing this, the generator generates electricity. in this action, the energy transfer taken place is kinetic to electric energy

The answer is d.potassium