Company A ships 1000 parts to company B each day. Company B samples 10 parts from each shipment. Company B uses a scoring system, below 6.2 is nonconforming. If one or more parts are nonconforming the entire shipment is rejected and returned to Company A. Parts test scores produced by company A follow a mean of 7 and standard deviation of 0.30. Over the past 20 days (20 shipments), four have been rejected & returned back to company A. Determine if there is a problem with the parts at company A.