This cause of weathering occurs when rocks change color due to a chemical
reaction with oxygen

Which of the following processes does the body not use protein to perform? a. repairing muscles b. producing hormones c. making hemoglobin d. creating amino acids

Warming up prepares the body for exercise in what way? a. muscularly b. cardiovascularly c. neurologically d. all of the above

Avirus consisting of a single strand of rna, which is transcribed into complementary dna, is a ) proteaseb) retrovirusc) rna replicase virusd) nonenveloped virus