One way to get consistent, valid data is to A. be sure that instruments are calibrated properly.
B. use simple instruments to make measurements.
C. select the best data to place into data tables.
D. make the measurements as quickly as possible.

thymine. in rna, thymine is replace by uracil

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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