A certain logician, though absolutely brilliant in theoretical matters was extremely unobservant and highly absent minded. He met 2 beautiful twin sisters named T(eresa) and L(enora). T always told the truth and L always lied. He married one of them, but forgot to find out her first name!

a. The logician met one of the two sisters at a logic conference, and wanted to know whether she's his wife. What short yes/no question can he ask?

b. A few days later, he again met one of them, and this time wanted to know the first name of his wife. What short yes/no question can he ask?

c. What if the logician wanted to know both pieces of information, the identity of the sister he met and the name of his wife. Can he ask a better question?