Mean/Standard Deviation question

I need help on this question, I don't know what equation to use to find the solution.

Suppose that the wrapper of a certain candy bar lists its weight as 2.13 ounces. Naturally, the weights of individual bars vary somewhat. Suppose that the weights of these candy bars vary according to a normal distribution with a mean 2.2 ounces and standard deviation 0.04 ounces.

Question 1) If the manufacturer wants to adjust the production process so that only 1 candy in 1000 weights less than the advertised weight, what should the mean of the actual weights be(assuming that the standard deviation of the weights remain 0.04 ounces)?