Task: Question Answering
Input (English): Problem: a milk man has 40 liters of milk. if he mixes 5 liters of water, which is freely available, in 20 liters of pure milk. if the cost of pure milk is rs. 18 per liter, then the profit of the milkman, when he sells all the mixture at cost price is :
Options: a. 20 %, b. 25 %, c. 45 %, d. 18 %, e. none of these
Output (English): c