Answer: A) All matter and energy were contained inside the small point.
Explanation: The theory that all matter and energy in the universe expanded from one condensed point (this is called the big bang theory) is the generally accepted explanation of the origins of our universe. Thought increasing amounts of doubt have been cast upon this theory in the last decade.
Answer:
θ = 30⁰
Explanation:
We have been given two wave displacement equations,
........(1)
........(2)
The waves will have same displacements when 
(say)
Therefore, operating (2) - (1), we get,
or, 
(since, sin 30⁰ = 0.5)
We can check the answer by putting 
in equations (1) and (2),
Answer:
atoms
Explanation:
All matter is made of elementary particles called "atoms".
Multiply by (1000 meters / 1 km).
Then multiply by (1 hour / 3600 seconds).
Both of those fractions are equal to ' 1 ', because the top
and bottom numbers are equal, so the multiplications
won't change the VALUE of the 72 km/hr. They'll only
change the units.
(72 km/hour) · (1000 meters / 1 km) · (1 hour / 3600 seconds)
= (72 · 1000 / 3600) (km·meter·hour / hour·km·second)
= 20 meter/second
