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IV. (10 points) We are running Sequential Search on an array of size n, and we know that the item we are searching for is definitely present in the array. The probability of finding it in the last position in the array is 1/5, and the probability of finding it in the next to last position in the array is also 1/5. The probabilities of matching the search key with each of the other items are all equal. The average case complexity function for Sequential Search under these conditions, A(n)