$a_{1}$= 81.33 $a_{2}$= –19
and $a_{ j }$ = $a_{ j-1 }$ - $a_{ j-2 }$ for j ≥ 3
$a_{3}$ = $a_{2}$ - $a_{1}$ = -19 - 81.33 = -100.33
Similarly,
$a_{4}$= $a_{3}$ - $a_{2}$ = -100.33 -(-19) = –81.33
$a_{5}$ = 19
$a_{6}$ = 100.33
$a_{7}$ = 81.33
$a_{8}$ = –19
Here we can clearly see that the sequence repeats itself after every 6 terms.
Sum of the first 6 terms of the sequence = 0
Thus, the sum of the first 6000 terms of this sequence = 0
The sum of the $6001^{st}$ and $6002^{nd}$ terms = 81.33 – 19 = 62.33
Hence,Option(3)62.33 is the correct choice.