Answer:
Step-by-step explanation:
C = πd. An equivalent formula is C = 2πr.
Solving the first equation for π, we get π = C/d. Solving the second equation for r, we get π = C / (2r)
Answer:
The complete area of the given figure is 
Step-by-step explanation:
Total number of rows = 2
Squares in each row = b
So, the total number of squares in 2 rows = 2 x ( Squares in 1 row ) = 2 x b
Also, side length of 1 square = b cm
As we know, AREA OF SQUARE = SIDE x SIDE
So here, area of 1 square = Side x side = b cm x b cm = 
⇒ The area of total (2b) squares = 2 b x ( Area of 1 square)

Hence, the complete area of the given figure is 
The surface area of the cone is 
Explanation:
The diameter of the cone is 10 cms
Thus, the radius of the cone is given by

The slant height of the cone is 12 cms
The formula for surface area of the cone is given by

Substituting the values, we get,




Thus, The surface area of the cone is 
I hope this explains it:
(Work and info in attachment)
Answer: 10
Imagine you have 2 slots or boxes that are empty. They represent the possible choices for the letter you pick. For example, you can place B in slot 1 and D in slot 2. There are 5 choices for slot 1 (A,B,C,D,E) and four choices for slot 2. Why 4? Because after we pick the letter for slot 1, we have one less letter to pick from. We can't reuse that letter.
Now multiply those values 5 and 4 to get 20. There are 20 different ways to pick a pair of letters from a pool of 5 total. However, order does NOT matter because the segment AB is the same as BA. Since order doesn't matter, we are doubly counting when we shouldn't. In other words, our count is two times higher than it should be. Instead of 20 pairs, it's actually 20/2 = 10 pairs. That's why the answer is 10.
The list of 10 segments are: {AB,AC,AD,AE,BC,BD,BE,CD,CE,DE}
Side note: you can use the nCr combination formula with n = 5 and r = 2 to get the same answer.