21.   A right prism has a triangular base whose sides are 13cm, 20cm and 21cm. if the altitude of the prism is 9cm, then its volume is A)     1314 cm³ B)      1143 cm³ C)      1413 cm³ D)     1134 cm³ * 22.   Articles are marked at the price which gives a profit of 25%. After allowing a certain discount the profit reduces to 12 and 1/2 %. The discount percent is A)     12% B)      12.5% C)      11.1% D)     10%* 23.   A and B are centres of two circles of radii 11cm and 6cm, respectively. PQ is a direct common tangebt to circle, if  AB =13cm, then length of PQ   will be A)     12cm* B)      8.5cm C)      13cm D)     17cm 24.   300 grams of sugar solution has 40% of sugar in it. How much sugar should be added to make it 50% in the solution ? A)     80 gm B)      40 gm C)      10 gm D)     60 gm* 25.   There is a wooden sphere of radius 6√3 cm. the surface area of the largest possible cube cut out from the sphere will be A)     646√3 cm² B)      462 cm² C)      *864 cm² D)     464√3 cm² 26.   If the buckets of water are removed from a cubical shaped water tank completely filled with water , 1/3 of the tank remains filled with water. The length of each side of the tank is 1.2 m. Assuming that all buckets are of the same measure, then the volume (in litres) of the contained by each bucket is A)     18* B)      12 C)      16 D)     15 27.   Ram sold two horses at the same price. In one he gets aprofit of 10% and in the other he gets a lossof 10% . then Ram gets A)     1% profit B)      *1% loss C)      2% loss D)     No loss or profit 28.   The value of (cosec a- sin a)(sec a- cos a)(tan a+ cot a) A)     1 B)      4 C)      2 D)     6 29.   AB and CD are two parallel chords of a circle of lengths 10 cm and 4 cm respectively . if the chords are on the same side of the centre and the distance between them is 3 cm, then the diameter of the circle is A)     √29cm B)      *2√29cm C)      2√21cm D)     √21cm 30.   A telegraph post is bent at a point above the ground due to storm. Its top just touches the ground at a distance of 10√3 m from its foot and makes an angle of 30ᶱ with the horizontal. Then height (in metrez) of the telegraph post is A)     20 B)      25 C)      30* D)     24