Task: Question Answering
Input (English): Problem: salad dressing p is made up of 30 % vinegar and 70 % oil, and salad dressing q contains 10 % vinegar and 90 % oil. if the two dressings are combined to produce a salad dressing that is 18 % vinegar, dressing p comprises what percentage of the new dressing ?
Options: a. 20 %, b. 30 %, c. 40 %, d. 50 %, e. 60 %
Output (English): c