An atom of carbon has a radius of and the average orbital speed of the electrons in it is about .Calculate the least possible uncertainty in a measurement of the speed of an electron in an atom of carbon. Write your answer as a percentage of the average speed, and round it to significant digits.

High-pressure liquid chromatography (hplc) is a method used in chemistry and biochemistry to purify chemical substances. the pressures used in this procedure range from around 500 kilopascals (500,000 pa) to about 60,000 kpa (60,000,000 pa). it is often convenient to know the pressure in torr. if an hplc procedure is running at a pressure of 1.03×108 pa , what is its running pressure in torr?