Select the statements that correctly describe how a barometer measures pressure. a. Pressure exerted by the atmosphere is equal to pressure exerted by the column of mercury.
b. The pressure exerted by an enclosed gas is equal to the height difference of a column of mercury in a U-tube.
c. A column of mercury inverted in a dish of mercury measures pressure exerted on the open surface of the mercury.
d. The diaphragm changes shape in response to exerted pressure.