Question

12.If the radius of the sphere is 21 cm, then its volume is _______ 13.The measure of the angle which is twice its complement is ________

Answer 1

Answer:

Step-by-step explanation:

38808 cm^3

Answer 2

$\bf\huge\blue{\underline{\underline{ Questions : }}}$

12.If the radius of the sphere is 21 cm, then its volume is _______

13.The measure of the angle which is twice its complement is ________

$\bf\huge\blue{\underline{\underline{ Solutions : }}}$

12)

★ Given that,

• $\tt\:\implies Radius_{(Sphere)} = 21\:cm.$

★ To find,

• $\tt\:\implies Volume\:of\:Sphere = ?$

★ Formula :

$\boxed{\tt{\red{ Volume\:of\:Sphere = \frac{4}{3} \times \pi r^{3} }}}$

$\bf\:\implies \frac{4}{3} \times \frac{22}{7} \times 21 \times 21 \times 21$

$\bf\:\implies 4 \times 22 \times 21 \times 21$

$\bf\:\implies38808$

$\underline{\boxed{\bf{\purple{\therefore Volume\:of\:Sphere = 38808\:cm^{3}}}}}\:\orange{\bigstar}$

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13)

★ Given that,

• The measure of the angle which is twice its complement is

★ To find,

• The angle.

★ Let,

• The angle be x°
• Complementary angle be 90 - x.

★ According to the question,

$\bf\:\implies x = 2(90 - x)$

$\bf\:\implies x = 180 - 2x$

$\bf\:\implies x + 2x = 180$

$\bf\:\implies 3x = 180$

$\bf\:\implies x = \frac{180}{3}$

$\bf\:\implies x = 60$

$\underline{\boxed{\bf{\purple{ \therefore The\: measure\: of \:the \:angle \:which \:is\: twice\: its \:complement \:is\: 60\degree.}}}}\:\orange{\bigstar}$

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