Certified Maintenance & Reliability Professional (CMRP) Practice Exam

The correct choice involves Hertz and Decibels, as these units are specifically designed to measure sound and noise levels. Hertz is a unit of frequency that describes how many cycles of sound waves occur per second, thus indicating the pitch or tone of the sound. Decibels, on the other hand, measure the intensity or loudness of sound. The decibel scale is logarithmic, meaning every 10-decibel increase represents a tenfold increase in intensity, making it particularly suitable for expressing the vast range of sound levels we encounter in everyday life.

Other measurement units listed do not apply to sound and noise levels. Watts and Volts relate to electrical power and voltage, respectively, which are not relevant in the context of acoustics. Pascals could pertain to sound pressure being a physical quantity, yet they are not as commonly used in general conversations about sound levels when comparing volumes. Ohms and Amperes are units of electrical resistance and current, respectively, neither of which provides insight into noise or sound measurement. Thus, Hertz and Decibels aptly capture the characteristics of sound waves and are the appropriate units for quantifying sound and noise levels.