By definition, the number
is the ratio between the circumference and the diameter:

This implies that

And so your circumference is 
25x and 4 hours. Hope it’s right
Answer:
105
Step-by-step explanation:
The interior angle for R is supplementary to the 155 degree angle
(they add to 180)
180-155=25
The sum of the interior angles of a triangle is always 180
180-50-25= 105
I feel like it might be the second one