How do I solve this using standard error

4. According to an article from huffingtonpost.com, some experts believe that 20%of all freshwater fish in the United States have such high levels of mercury that they are dangerous to eat. Suppose a fish market has 250 fish that we consider randomly sampled form the population of edible freshwater fish. Use the Central Limit Theorem (and the empirical rule) to find the approximate probability that the market will have a proportion of fish with dangerously high levels of mercury that is more than two standard errors above 0.20. (Assume that the conditions for using the CLT have been met ). . wol of a. ssie 9/grod ONT