Answer:
They developed during the Cambrian time period, which was around 530 million years ago.
Explanation:
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Answer:
Explanation:
Given
Each student exert a force of 
Let mass of car be m
there are 18 students who lifts the car
Total force by 18 students 
therefore weight of car 
mass of car 
(b)
C. A 1200kg car is going 15m/s
Diagram D. shows the sound waves generated by a siren
that is moving with constant speed to the left.
A sound wave is the sample of disturbance caused by the movement of strength journeying thru a medium because it propagates far away from the supply of the sound. Sound waves are created by using object vibrations and bring strain waves, for example, a ringing cellular phone.
Sound waves fall into three classes: longitudinal waves, mechanical waves, and strain waves. keep studying to find out what qualifies them as such. Longitudinal Sound Waves A longitudinal wave is a wave wherein the movement of the medium's debris is parallel to the course of the energy transport. Sound propagates via air or different mediums as a longitudinal wave, in which the mechanical vibration constituting the wave occurs along the direction of propagation of the wave.
Learn more about sound waves here:-brainly.com/question/1199084
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