The resistance R of a certain rype of resistor is R = 0.003T4 − 2T + 100 where R is measured in ohms and the temperature T is measured in degrees Celsius. Use a computer algebra system to find the critical number of the function. Round numerical values in your answer to the nearest whole number. T = 18∘ T = 13∘ T = 7∘ T = 4∘ T = 6∘