Can someone help me with these 2 polygons and how to figure out a circumference

The circumference of a circle is found by using the equation: C= 2 x PI x r

Both circles have r = 1

Circumference = 2x 3.14 x 1 = 6.28.

Diameter is 2 times the radius= 2x1= 2

The ratio of the circumference to the diameter = 6.28 / 2 = 3.14 which is the value of PI

the equation cos(35) =a/25 can be used to find the length of bc what is the length of bc? round to the nearest tenth

step-by-step explanation:

dc=6 square root of 3 and ac is 12 square root 3

c and d

step-by-step explanation:

square root of 3/2 = 18/c

cross multiply to get 18*2=√3*c

36/√3 * √3/√3 = c

c= 36*√3/3

c=12√3