Voltages measured with a thermoelement pair are 0.8mV for (20-0)C and 27.07mV for (712.5-20)C. In the measurement made with this thermoelement, after the measurement point temperature is calculated as 80C, it is seen that the temperature at the reference end is greater than 0C. To eliminate the error in measurement, the measuring tip was immersed in a water- ice mixture and a deviation of 0.1mV was observed on the millivoltmeter. How much does the first measured value of 80C actually weigh?