The Fish and Game Department stocked a lake with fish in the following proportions: 30% catfish, 15% bass, 40% bluegill, and 15% pike. Five years later it sampled the lake to see if the distribution of fish had changed. It found that the 500 fish in the sample were distributed as follows: Catfish, Bass, Bluegill, pike
112, 95, 210, 83

Required:
a. In the 5-year interval, did the distribution of fish change at the 0.05 level?
b. Find the value of the chi-square statistic for the sample.