Which statements is the best definition of of weather?

Is kilogram a noun? What did Richard feynman's invent? Ordinary light waves vibrate in all directions light that vibrates only in a specific plane is said to be? What is the relationship between g and acceleration of a pendulum? What is propulsive force of a rocket engine called? What is the maximum speed a human can survive? What is effort force on a lever? What is mechanical advantage of screw Jack? Is a meter slightly shorter than three feet? If you exert a force on an object in motion you will change its .? What is the period of the wave having amplitude 1.25cm and wavelength 2cm? How much pressure does a diver experience at 30 meters depth in salt water? Why do rubber balloons lose air faster than plastic balloons? How much energy would be absorbed as heat by 75g of iron when heat from 295k to 301k? Why should the top surface of the reflecting hood be a light shiny surface rather than a dark Mat surface? Do protists make energy? Where should a person in the heat escape position place their hands? What is the process by which heat transfers from one particle of matter to another which the particles collide? How did water fountains work in the old days? What does einsteinium look like?

Which statements is the best definition of of weather?