39) Number of identical terms in the sequences 2, 5, 8, 11, .... upto 100 terms and 3, 5, 7, 9, 11, .... upto 100 terms, are

43) concentric circles of radii 1, 2, 3, .... , 100 cm are drawn. The interior of the smallest circle is coloured red and the angular regions are coloured alternately green and red, so that no two adjacent region are of the same colour. Then, the total era of the green region in sq.cm is equal to

88) If sum of the first 2n terms of an AP series 2, 5, 8, ... is equal to the sum of the first n terms of the AP series 57, 59, 61, ..., then n equals

93) If the sum to 2 n terms of the AP 2, 5, 8, 11, ... is equal to the sum to n terms of the AP 57, 59, 61, 63, ..., then n is equal to