Your answer would be true. Because if we didn't have those pieces of evidence, we wouldn't know about a lot of the ancient civilizations that we know today without that. Small pieces of evidence like that can help us to determine how they lived, or what they used to do, or even what they ate.
Answer: A
Explanation: We know that f=p*n
f=50*300=15000 Hz = 15kHz.
Have a great day! <3
Answer:
-0.912 m/s
Explanation:
When the package is thrown out, momentum is conserved. The total momentum after is the same as the total momentum before, which is 0, since the boat was initially at rest.
where 
are the mass of the child, the boat and the package, respectively. 
are the velocity of the package and the boat after throwing.
Gravitational potential energy = mass × gravity × height
Ep = (4)(9.81)(3)
Energy = 117.72 Joules
= 1.2x10^2 Joules
The starting point for measuring motion is called : The Reference Point.
