The mean amount purchased by a typical customer at Churchill's Grocery Store is $27.50 with a standard deviation of $7.00. Assume 6 the distribution of amounts purchased follows the normal distribution. For a sample of 68 customers, answer the following questions. 03752 ock a. What is the likelihood the sample mean is at least $30.00? (Round your z value to 2 decimal places and final answer to 4 decimal places.) Prunarity b. What is the likelihood the sample mean is greater than $26.50 but less than $30.00? (Round your z value to 2 decimal places and final answer to 4 decimal places.) Pubbly