Which is a result of chimical weathering

a rock that has lost its outer layer

a rock that has been broken into tiny similar pieces

a rock that has changed into one or more compounds

a rock that has been split into two parts

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Researchers conducting web-based research have trouble controlling who actually answers their on-line questionnaires, which places limits on their research due to the possibility of a. biased samples. b. the barnum effect. c. researcher bias. d. research participant bias.