Answer:
A crest is the highest point of a wave.
A trough is the lowest point of a wave.
Infrasound is sound below the limit that humans can hear, below 20 Hz.
Ultrasound is sound above the limit that humans can hear, above 20,000 Hz.
Answer:she errored
Step-by-step explanation:
The answer is 0.73 because in 0.975 the value of digit 7 is 7/100 ,10 times of 7/100 is 7/10 and the value of 7 in 0.73 is 7/10 ;.tenth value.