The owner of a store wants to investigate the relationship between the age group of sales assistants and the customer experience reviews of those sales assistants. The results are summarised in the following table: Age group of sales assistant 15to$ 30tos 45tos Over 30 45 60 60 years years yea rs years Total Customer _ Excellent 28 25 32 35 120 serwce Average 35 54 48 58 l 95 Poor ?' TO 12 6 35 Total 70 89 92 99 350 a) Calculate the probability of randomly selecting a sales assistant that provided excellent customer service. b) Calculate the probability of randomly selecting a sales assistant that provided average customer service or is 30 to less than or equal 45 years old. c] Are the events, \"Excellent customer service" and \"over 60 years\