Hydrogen fuel cells that operate at lower temperatures use more expensive platinum electrode catalysts. what to make up for the higher-cost electrodes? a) they use a cheaper fuel. b) they operate at a higher efficiency. c) they use a reaction that is not redox. d) they produce fewer emissions.

Select the correct text in the passage. which sentences describe examples of sustainable living? i live in an old apartment building downtown, but my company is based in an office park on the outskirts of the city. i drive an old car that needs to be replaced. i plan to buy a hybrid for better gas mileage, but for now i am able to carpool with a couple of friends from work. the drive to the office park is about 45 minutes each way, but we do get to work in a modern building. the architects just received a leed certification for the design.

What is a possible quantum number set for an electron in the 3s orbital of a magnesium atom

Explain in detail of the four major scientific developments that spurred the formulation of the plate tectonics theory