Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.

[Q]: Problem: 18.05 ã — 0.001 = ?
Options: a. 0.1805, b. 0.01805, c. 1.805, d. 0.001805, e. none of these
[A]: b


[Q]: Problem: find the sum of first 89 odd numbers
Options: a. 7921, b. 4800, c. 7900, d. 4980, e. 4960
[A]: a


[Q]: Problem: a and b invests rs. 8000 and rs. 12000 in a business. after 4 months, a withdraws half of his capital and 2 months later, b withdraws one - third of his capital. in what ratio should they share the profits at the end of the year ?
Options: a. 32: 99, b. 82: 31, c. 8: 15, d. 34: 89, e. 35: 21
[A]:
c