Can someone explain how to do this: If you put 10 in to the function f(x) = 2x, what would be the output?

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Im so lost-

Which approach to the theory-and-research cycle does the following sequence reflect: (1) specific observations suggest generalizations, (2) generalizations produce a tentative theory, (3) the theory is tested through the formation of hypotheses, and (4) hypotheses may provide suggestions for additional observations?

Aiden buys two bags of chips at $1.09 each and a 20 ounce soda for $1.20 at the gas station. he knows that the state tax is 5.5. how much change will he receive from a $5 bill?

Select the correct answer what is the 10th term of the geometric sequence 3,6, 12, 24,48 a. 512 b. 3,072 c. 768 d. 1,536