A Lean Six Sigma team is trying out a new forming tool to reduce variability in a process that creates hamburgers patties in a fast food restaurant. One of the significant dimensions has a process standard deviation of 0.35 mm. The team needs to know how many samples to collect in order to achieve an estimate of the mean with precision of + or - 0.15 mm, with 95% confidence. What sample size is required to meet this goal?