This is for physical science, pls dont use g00gIe
What is a vector?

A vector is an object that has both a magnitude and a direction. We can picture a vector as a directed line segment, whose length is the magnitude of the vector and with an arrow indicating the direction.

~iwa-chan

in theory, limestone is composed principally of the compound calcium carbonate - caco3, but in reality this compound is deposited in conditions involving a number of other compounds as impurities so it ends up being a mixture of many compounds.

hope this : -)

tony (lordcaos066)

the awnser is group 12