A right triangle with sides 3 cm, 4 cm and 5 cm is rotated the side of 3 cm to form a cone. The volume of the cone so formed is:
A.
12 cm3
B.
15 cm3
C.
16 cm3
D.
20 cm3
2.
In a shower, 5 cm of rain falls. The volume of water that falls on 1.5 hectares of ground is:
A.
75 cu. m
B.
750 cu. m
C.
7500 cu. m
D.
75000 cu. m
3.
A hall is 15 m
long and 12 m broad. If the sum of the areas of the floor and the
ceiling is equal to the sum of the areas of four walls, the volume of
the hall is:
A.
720
B.
900
C.
1200
D.
1800
4.
66 cubic centimeters of silver is drawn into a wire 1 mm in diameter. The length of the wire in meters will be:
A.
84
B.
90
C.
168
D.
336
5.
A hollow iron pipe is 21 cm long and its external diameter is 8 cm. If the thickness of the pipe is 1 cm and iron weighs 8 g/cm3, then the weight of the pipe is:
cm3