Fig.12.3 depicts an archerytarget marked with its five scoring regions from the centre outwards as Gold,Red,Blue,Black and White.The diameter of the regions representing Glod score is 21 cm and each of the bands is 10.5 cm wide.Find area of each of the five scoring regions.

A sector from teo concentric circle is shown in Fig.14.If the radii of the circles are respectively 3.5 cm and 7 cm,find the area of the shaded region in the figure.

Find the area of the shaded region in the given figure, where ABCD is a square of side 10cm and semi-circles are drawn with each side of the square as diameter.

A wooden article was made by scooping out a hemisphere from each end of a solid cylinder,as shown in Fig.13.11.If the height of the cylinder is 10 cm,and its base is of radius 3.5. find the total surface area of the article.

If Fig.12.30,OACB is a quadrant of a circle with centre O and radius 3.5 cm.If OD=2 cm.find the area of the(ii)shaded region

AB and CD are respectively arcs of two concentric circles of radii 21 cm and 7 cm and centre(see Fig.12.32).If angleAOB=30^@ ,find the area of the shaded region.

In Fig 12,PS is a diameter of a circle whose radius is 6 cm.Two points Q and R are taken on PS such that PQ=QR=RS.Two semicircles are drawn with PQ and QS as their respective diameters as shown in the figure.Find the perimeter and the area of the shaded region shown in figure. (pi=3.14)

The area of an equilateral triangle ABC is 17320.5cm^2 .With each vertex of the triangle as center,a circle is drawn with radius equal to half the length of the side of the triangle(seeFig.12.28).Find the area of the shaded region.(use pi=3.14 and sqrt3=1.73205 )

Find the area of the shaded region in Fig.12.21,,where a circular arc of radius 6 cm has been drawn with vertex O of an equilateral triangle OAB of side 12 cm as centre.

In Fig.12.25,ABCD is a square of side 14 cm.with centres A,B,C and D,four circles are drawn such that each circle touch externally two of the remaining three circles.Find the area of the shaded region.