List rocks from oldest to youngest granite, pegmatite, sandstone, besalt, limestone, shale and sandstone

What percentage of light hits earth's surface directly?

Types of scientific inquiry that biologist engage in that cannot be completely controlled

The greenhouse effect a. something that has occurred for millions of years b. an unnatural phenomenon caused by humans that maintains earths temperature range. c. the results of the differences in the angle of the suns rays d. an unnatural phenomenon that causes heat energy to be radiated back into the atmosphere