For the following questions answer them individually
A, B and C together can complete a piece of work in 30 days. A takes twice as long as B and C together take to complete the work while B takes twice as long as A and C together to complete the same work. The number of days C alone needs to complete the work is
If the area of a sector in a circle is $$\frac{77}{3} cm^2$$ and if the radius of the circle is 7 cm, then the sectorial angle is
The perimeter of a rhombus is 40 cm and one of its diagonals is 16 cm. Then the area (in $$cm^2$$) of the rhombus is
A hollow road-roller 63 cm wide with circumference of 440 cm is made up of iron, If its thickness is 4 cm, then the volume (in $$cm^2$$) of the metal used is
The dimensions of a rectangular solid S are $$4 \times 9 \times k$$. If the volume of S is the same as the volume of a cube of side 6, then the value of k is
A door is in the shape of rectangle surmounted by a semicircle on its breadth. If the rectangle dimensions are 10 ft $$\times$$ 7 ft. then the area of the cross-section of the door (in sq. ft.) is
A solid cylinder of height 6 cm and base radius 2 cm is melted and cast into a cone of the same base radius as that of the cylinder. Then the height of the cone (in cm) is
A cylinder is of height h and base radius r. If t denotes the total surface area and v its volume, then $$\frac{t}{2v} =$$