Sand grains are __________ particles of gravel.

The type of rock formed from the cooling and solidification of magma or lava is _________.

Some of the earliest evidence in support of the theory of plate tectonics included similarities in the following feature(s) observed on opposite sides of the Atlantic Ocean:

The principal process whereby lithogenous sediments reach the middle of the ocean basins is transport by ____________.

Sea breezes __________.

Estuaries formed __________.

Carbon dioxide __________.

pH is a measure of ___________.

The largest reservoir of water in the hydrosphere is (are) the__________.

The greenhouse effect is the heating of Earth’s surface and lower atmosphere caused by strong absorption and emission of __________ radiation by certain gaseous components of the atmosphere.