Question

Please answer this please 2 questions please

Answer 1

(1)

ratio of radii of two spheres

r1 : r2 = 2: 3

ratio of their areas

= r1^2 : r2^2 = (2)^2 : (3)^2

= 4 : 9

ratio of their volumes

= (r1)^3 : (r2)^3 = (2)^3 : (3)^3

= 8 : 27

question.no. (2)

radius of hemisphere = 10cm

total surface area = 3πr^2

=3 ×3.14× (10)^2

= 942cm^2

Answer 2

Answer:

(1) 4:9, 8:27

(2) 942 cm²

Step-by-step explanation:

(1)

Given ratio = 2:3

Ratio of their surface areas:

= 4πr₁²/4πr₂²

= r₁²/r₂²

= 4/9.

∴ Therefore,ratio of their surface areas = 4 : 9

Ratio of their volumes :

= 4πr₁³/4πr₂³

= r₁³/r₂³

= 8/27

∴ Therefore, Ratio of their volumes = 8 : 27.

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(2)

Given, radius = 10 cm.

Surface area of hemisphere:

= 3πr²

= 3 * (3.14) * (10)²

= 942 cm²

∴ Therefore, Surface area of hemisphere = 942 cm²

Hope it helps!