<em>number of waves that pass a given point in one second is called <u>frequency..</u></em>
Explanation:
We know that the sky appears to us like a sphere called as celestial sphere which appears to rotate around an imaginary axis because of Earth's rotation. Since the axis cuts the celestial sphere at celestial poles all the object seems to circle around the celestial poles.
Condition 1: The stars rise and set perpendicular to the horizon
The observer is at the equator
Condition 2: The stars circle the sky parallel to the horizon
The observer is at the Pole of the Earth
Condition 3: The celestial equator passes through the zenith
The observer is at the equator
Condition 4: In the course of a year, all stars are visible
The observer is at the equator
Condition 5: The Sun rises on March 21 and does not set until September 21 (ideally)
The observer is at North Pole
Answer:

Explanation:
From the question we are told that:
Height of window 
Height of window off the ground 
Time to fall and drop
Generally the Newton's equation motion is mathematically given by

Where



Generally the Newton's equation motion is mathematically given by

Where





Therefore the ball’s initial speed

Answer:
I think it's 2 the photo is hard to tell what they are exactly talking about.