Answer:
The truck's speed is 4.04 m/s.
Explanation:
Given that,
Emit frequency = 600 Hz
Beat = 7.00 beat/sec
We need to calculate the truck's speed
Using formula of speed

Where, v = speed of sound
Put the value into the formula



Hence, The truck's speed is 4.04 m/s.
Answer:
Flutter
Explanation:
Flutter is a type of arrhythmia that causes very fast and regular ryth of the atria of about 250 beats per minute.
Arrhythmia can be defined as any sort of irregularity heart rate or rhythm is also called as dysrhythmia.
Arrhythmias can be categorized as heart block, bradycardia, tachycardia, fibrillation, flutter, sick sinus syndrome, and is diagnosed by Electrocardiography.
In Flutter, the heart chambers do get sufficient time to get filled with blood completely prior to next contraction.
D. distance
A light-year is the distance light would travel in 1 year.