If the sum of the first $n$ terms of a series be $5{n^2} + 2n$, then its second term is
$7$
$17$
$24$
$42$
(b) ${T_2} = {S_2} – {S_1}$
= $5{(2)^2} + 2(2) – \{ 5{(1)^2} + 2(1)\} = 24 – 7 = 17$.
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The sum of all two digit numbers which, when divided by $4$, yield unity as a remainder is
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