Two brands of resistance thermometers are available to a laboratory. To decide which brand to buy, they initially test six thermometers of each brand, with the following measured values when the known standard is 950 mv:

Brand A: 938, 954, 947, 961, 951, 944 Brand B: 931, 948, 967, 973, 947, 964

(a) Does Brand A produce resistance thermometers that meet the standard?

(b) Does Brand B meet the standard?

(c) Do the means of the two brands differ significantly?