Question 24General Subjects - QMED

The correct answer is D) Compound gauge. A compound gauge is capable of measuring and displaying both positive and negative pressures. This is because it has two independent pressure sensing elements - one for positive pressure and one for negative (vacuum) pressure. The gauge then combines the readings from these two elements to display the overall pressure, which can be positive, negative, or zero. The other options are not capable of measuring both positive and negative pressures. A simplex gauge only measures positive pressure, a differential pressure gauge measures the difference between two positive pressures, and a duplex gauge has two independent pressure gauges for monitoring two separate positive pressure systems.