Abattery manufacturer was considering changing suppliers for a particular part. the purchasing manager required that the average cost of the part be less than or equal to $32 in order to stay within budget. a sample of the 32 initial deliveries had a mean of the new product upgrade price of $28 with an estimated standard deviation of $3. based on the data provided, the z value for the data assuming a normal distribution is?
a) 0.67
b) 1.33
c) 2.67
d) 4.33