Motion of a star across the sky?

Question

the following is a chart but it needs to be on a graph to determine the answer i need the final answers i have no idea how to arrive at the final answer

I need
the Angular speed of star in degrees per hour
Length of day in hours


Time----------------Angle
O hours 00 minutes--------20.0 degrees
0 hour 30 min---------24.4 degrees
1 hour 00 min------28.2 degree
1 hour 30 min ------33.4 degree
2 hour 00 min--------37.5 degree
2 hour 30 min------41.8 degree
3 hour 00 min-------45.9 degree
3 hours 30 min-----49.5 degree
4 hours 00 min-----53.0 degree
4 hour 30 min--------57.8 degree
5 hour 00 min-------60 degree
5 hour 30 min-----65.3 degree
6 hours 00 min .....69.9 degree
6 hours 30 min----72.8 degree
7 hours 00 min------76.4 degree
7 hours 30 min-------81.6 degree
8 hours 00 min-------83.9 degrees

I NEED the answer...... i have been trying but keep getting the wrong answer... i need the final answer who ever gives the correct answer get 10 points

Answer 1

One way would be to plug the values into a couple columns in Excel.
0.0, 20
0.5, 24.4
1.0, 28.2
1.5, 33.4
...
7.5, 81.6
8.0, 83.9

Select the columns and create a graph as an X-Y scatter. Tell Excel to add a linear trend line, also tell it to turn on the option to display the formula of the trend line.

If you do this, the graph will look like the first attachment.

The formula works out to about:
y = 8.0049x + 20.992

In other words, about 8 degrees of angle for every hour.

You could do this all manually using a least squares fitting (second link). Not knowing much about what math you are expected to know, its hard to give you a better answer.

As an estimate, you could just take the end points. The first point is 0, 20 and the last point is 8, 83.9. The angle changes 63.9 degrees over 8 hours. Dividing you get 7.9875 degrees per hour, but I'd just round it to 8 degrees per hour again.

Answer 2

during the first hour, the star has moved 8.2 degrees. therefore, the angular speed of the star is 8.2 degrees per hour.