How have sea levels changed since 1900? A risen by 15–20 cm
B decreased by 10-15 cm
C risen by 20–24 cm
D risen by 12–15 cm

life would be meaningless without memes

about 40,000,000 results (0.81 seconds)  

search results

what do the different brain waves do?

explanation:

brainwaves are produced by synchronised electrical pulses from masses of neurons communicating with each other. brainwaves are detected using sensors placed on the scalp. brainwave speed is measured in hertz (cycles per second) and they are divided into bands delineating slow, moderate, and fast waves.

the most common type of reef is the fringing reef. this type of reef grows seaward directly from the shore. they form borders along the shoreline and surrounding islands.

it's c.us forest service