Please answer and explain

During the past many summers, Ben and Jerry have had tourists stay at their bed and breakfast. On average they receive 750 tourists and during the last summer, with a standard deviation of 60 tourists and a z-score for the last summer of business of 2.57. . How do you know that the last summer of business was not as good as usual? (1 mark) . How many tourists did they receive last summer? (1 mark)