15
1.
2.
3.
th
AN 1(c) 2(b) 3(a) 4(d) 5(c) 6(not in AP.as CD is not same) 7 (2.5hrs= 150min,an=150, n=29,so 29 day
S onwards) 8( sum of 12 calls= 180mins,time 2:48pm+3hrs =5:48pm,
9 (4/3),10( ), 11(X=1), 12(852),13(7p-13q=6), 14(an = a(33-23n)/10
,15.(3,6,9,12….. n=42, 15 layers)
3