9x^2 and 5x are like terms.

true
false

Iam so stuck. what is the worked out answer for this question?

The contents of 3838 cans of coke have a mean of x¯¯¯=12.15x¯=12.15. assume the contents of cans of coke have a normal distribution with standard deviation of σ=0.12.σ=0.12. find the value of the test statistic zz for the claim that the population mean is μ=12.μ=12.

With number 11 ( show how you got the answer)