Find the inverse please and thank you

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.

Find the balance at the end of 4 years if 1000 is deposited at the rate of

How do i do this? i don’t understand