Answer:

Step-by-step explanation:
The equation of a circle has the following format:

In which r is the radius(half the diameter) and the centre is the point 
Centered at the origin
This means that 
Passing through the point(0,10)
The radius is the distance of any point in which the circle passes to the centre.
Using the formula for the distance between two points.

So


With 98x50 its like there are 98 fiveties. In 97x 50 there are 97 fiveties. There is one more 50 in 98x50.
Answer:
1.44927536232
Step-by-step explanation:



now.. hmmm let's see, keeping in mind the template above
so, amplitude of 2, A=2, thus |A| = ±2, so, you can use either
and period of 4π, well, that simply means that
(a+b)(a-b) = a^2 - b^2
(1+5/6) (1-5/6) = 1^2 - (5/6)^2 = 1 - 25/36 = 36/36 - 25/36 = (36-25)/36 = 11/36
11/36 is your answer