Select the appropriate units for each property of a wave.
intensity:
amplitude:
frequency:

Intensity: Decibels

Amplitude: Meters

Frequency: Hertz

Explanation:

The Wave is not visible to eyes and they can easily propagate through vacuum. the average power travelling at a given period of time in a space is the intensity. Decibels is the measure of intensity. it is measured in the decibel scale. The wave's strength and the intensity gives the amplitude of wave. It is measured using meters.

The wave's amplitude and the energy has a direct proportionality.  The number occurrence of wave cycles per second refers to the frequency of wave. it is measured in hertz. it is also measured as the number of cycles that occurs per second.

answerscientific theory;

t = 1/400 h   ⇔ 0.0025 h ⇔ 9s ⇔ 0.15 m

any of the answers are correct.