Amanufacturer of potato chips would like to know whether its bag filling machine works correctly at the 406.0 gram setting. it is believed that the machine is underfilling the bags. a 40 bag sample had a mean of 405.0 grams. a level of significance of 0.02 will be used. is there sufficient evidence to support the claim that the bags are underfilled? assume the standard deviation is known to be 26.0.what is the conclusion?