well, from birth to your twentieth birthday that'll just be 20 years, so

With pythagorean theorem and working backwards, you do 8100-1225 to get 6875, you then get the square root of that to get x=82.91 or rounded to 82.92
Ok so we know that the distance around the circle (or circumference) is equal to the diameter times pi.
This means that

d being the diameter,
This means that:

= 12.00028271
= 12 m
So the diameter of the circle is 12 metres.
Hope this helped
B) (16 + 20)a - 18b
16a and 20a are both positive and 18b is the only negative it’s easier to add the positive with each other then the negative and a positive then add other positive
Hello,
Answer B
An exterior angle of a circle has like measure the half of difference of the arcs.
mes S=(85°-25°)/2=60°/2=30°