Coal is considered a nonrenewable resource because A) it can never be replaced
B) it comes from the impact of meteors with the Earth
C) it was mismanaged by humans; it used to be a renewable resource
D) it takes millions of years to form

Which of the following types of stars had the smallest initial mass? which of the following types of stars had the smallest initial mass?

Which of the following situations would most likely occur if a human-induced event caused the ocean water to become the same temperature around the world? deep ocean current circulation would increase salt distribution around the world's oceans. surface ocean current circulation would distribute heat around land masses at a faster rate. new, fresher water would float on top of dense salt water and limit thermohaline circulation. some land masses in the northern hemisphere would start to warm up over time, melting snow and ice. runoff of surface freshwaters and rainfall would no longer have an effect on the salinity of ocean waters.

Which of the following activities would conserve the most energy? installing a dimmer switch on a light using a blender instead of a food processor hanging clothes to dry on a clothesline instead of ironing them opening a window instead of turning on the air conditioning setting your computer's screen saver to turn on after less time has elapsed