100 students were interviewed about their favorite subject. 28 liked Mathematics, 31 liked Science, and 42 liked English. 9 liked both Mathematics and Science, 10 liked Mathematics and English, 6 liked Science and English and 4 liked all of the three subjects. 1. How many students liked Mathematics only? a. 9 c. 20 b. 13 d. 23 2. How many students liked English only? a. 25 c. 30 b. 28 d. 33​