(a) Describe how we can use (open) hashing to check whether all n records in a list are distinct. (b) Use the Poisson approximation to the binomial distribution to determine a formula for the expected number of comparisons required for this process from part (a) in terms of the number of records n he hash table size m, under the usual assumption that the hash addresses of distinct records are independent and uniform. If m and n are equal, is this process faster than just pre-sorting the records (based on any field) and determining if any records with equal keys in that field are actually equal