Grandma Gertrude's Chocolates, a family owned business, has an opportunity to supply its product for distribution trough a large coffee house chain. However, the coffee house chain had certain specifications regarding cacao content a it wishes to advertise the health benefits (antioxidants) of the chocolate products it sells. Past data indicate a standard deviation of 4%. If quality control inspectors wish to estimate the % cacao to within 1% of the true mean with 95% confidence, how many pieces of chocolate should they sample?