I don't understand how to solve for this with this much information

The distribution of actual weights of 8-ounce chocolate bars produced by a certain machine is Normal with mean 8.1 ounces and standard deviation 0.1 ounces. Company managers do not want the weight of a chocolate bar to fall below 7.85 ounces, for fear that consumers will complain. (a) Find the probability that the weight of a randomly selected candy bar is less than 7.85 ounces