Does anyone know how to answer this or what the answer is? my sister is having a hard time figuring this out with her tutor?

Its number four.Hope that helps feel free to ask me questions:)

Brainliest??

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 earth would become to overheated and everything alive on it will eventually die from overheating. plants will eventually die as well, water will evaporate, and it will be nothing but a hot planet without anything living on it.