Surface area SA:

Circumference C:

dividing this you get

and

Now let's input the radius

into the Surface area formula...
See the attached figure to better understand the problem
we know that
<span>The inscribed angle in a circle measures half of the arc it comprises.
</span>in this problem
the inscribed angle= ∠ACB
and the arc it comprises measures 180°
then
the ∠ACB=180°/2-------> ∠ACB=90°
<span>applying the Pythagorean theorem
</span>AC²+CB²=AB²-------> AB²=24²+7²-------> AB²=625------> AB=25 cm
the diameter of circle is AB
radius=25/2--------> r=12.5 cm
[the area of a half circle]=pi*r²/2------> pi*12.5²/2--------> 245.44 cm²
[area of triangle ABC]=AC*CB/2--------> 24*7/2-------> 84 cm²
[the area of the shaded region]=[the area of a half circle]-[area of triangle ABC]
[the area of the shaded region]=245.44-84-------> 161.44 cm²
the answer is
the area of the shaded region is 161.44 cm²
Answer:
<h2>
21 no sure what the "i" means</h2>
Step-by-step explanation:
Answer:
88 units
Step-by-step explanation:
BR || WN (Given)
Therefore,
(Alternate angles)
(Vertical angles)
(AA postulate)
(csst)
RN = OR + ON
RN = 32 + 56
RN = 88 units
Answer:

Step-by-step explanation:
GIVEN: A bibliophile plans to put a total of seven books on her marble shelf. She can choose these seven books from a mixture of works from Antiquity and works on Post-modernism, of which there are seven each.
TO FIND: If the shelf must contain at least four works from Antiquity, and one on Post-Modernism, then how many ways can he select seven books to go on the shelf.
SOLUTION:
Total number of books available 
As there must be at least
books on Antiquity and
on Post-modernism
Therefore,
when there are
Antiquity books and
on Post-modernism.
total ways of selection 
when there are
Antiquity books and
on Post-modernism.
total ways of selection 

when there are
Antiquity books on
books on Post-modernism.
total ways of selection 

Total ways of selection are 

Hence the total ways of selection such that there are at least
books on Antiquity and
on Post-modernism.