Figure 7.13 shows a toy. Its lower part is a hemisphere and the upper part is a cone. Find the volume and the surface area of the toy from the measures shown in the figure.(=3.14)

Given radius of cone ,r = 3 cm
Height of cone ,h = 4 cm
Radius of hemisphere, r = 3cm
Slant height of cone , l = √(h²+r²)
l = √(4²+3²) = √(16+9) = √25 = 5
Curved surface area of cone = rl
= ×3×5 = 15cm²
Curved surface area of hemisphere = (2/3)r³
= (2/3)×3³ = 18cm²
Surface area of toy = Curved surface area of cone+ Curved surface area of hemisphere
= 15+18 = 33 = 33×3.14 = 103.62cm²
Volume of cone = (1/3)r²h
= (1/3)×3²×4 = 12cm³
Volume of hemisphere = (2/3)r³
= (2/3)×3³ = 18cm³
Volume of toy = Volume of cone+ Volume of hemisphere
= 12+18 = 30 = 30×3.14 = 94.2cm³
Hence the surface area and volume of the toy are 103.62cm² and 94.2cm³ respectively.