And circle hour which I always equal to 90°

A circle or the circumference on a clock would be 360 degrees, half being 180 degrees, and a quarter being 90 degrees.

Step-by-step explanation:

Hope this helps! :D

 r represents a significant linear correlation.

Step-by-step explanation:

GIven : Linear correlation coefficient: r = 0.543

Sample size: n= 25

Significance levle:

Degree of freedom : n-2 = 25-2=23

Now, we check r critical value table for value with df = 23 and .

Critical value = ±0.396  [From r critical value table]

Since r = 0.543 > 0.396, that means there is significant linear correlation.

Hence,  r represents a significant linear correlation.