A set of 10 new questions in each round. Question: ( 1 of 10 ) If Linda can finish the work in 9 days and Charles can finish the same work in 13 days, then in how many days both can finish the work together? (A) 11 days (B) 22 days (C) 5 7/22 days or 5.318 days (D) 10 7/22 days or 10.318 days