A man accepts a position with an initial salary of ₹5200 per month.

We have,

the initial salary, a1 = ₹5200,

the salary of the second month, a2 = ₹5200 + ₹320 = ₹5520,

the salary of the third month, a3 = ₹5520 + ₹320 = ₹5840,

As, $a_{2}-a_{1}=5520-5200=320$ and $a_{3}-a_{2}=5840-5520=320$

i.e. $a_{2}-a_{1}=a_{3}-a_{2}$

So, $a_{1}, a_{2}, a_{3}, \ldots$ are in A.P.

Also, $a=5200, d=320$

(i) $a_{10}=a+(10-1) d$

$=5200+9 \times 320$

$=5200+2880$

$=8080$

So, the salary of the man for the tenth month is $₹ 8,080$.

(ii) $S_{12}=\frac{12}{2}[2 a+(12-1) d]$

$=6(2 \times 5200+11 \times 320)$

$=6(10400+3520)$

$=6 \times 13920$

$=83520$

So, the total earnings of the man during the first year is $₹ 83,520$.