Recall, I mentioned there are two potential sources of accuracy error. One occurs when you are using a device with a readout that converts some analog signal to a digital measurement; there will be some sort of accuracy associated with the instrument. These types of accuracy errors are reported in spec sheets as either full-scale errors or some accuracy error of the reading. In the case of analog measurement devices like the thermometer or ruler, for instance, obviously that type of accuracy error is not present. If there is no accuracy error posted on a spec sheet, the other potential source of accuracy error comes from you, the person taking the measurement. So if you believe that you misread the thermometer or something of that nature (wrote down the wrong temperature, etc.), that would be an accuracy error. If you recall from the homework, you were asked a question regarding the legitimacy of setting the accuracy error on the calipers to zero...basically this is the same situation.