solve these number problems. (a) i am a two-digit number less than 20. i am odd. The sum of my digits is 10. which number am i? (b) i am a two-digit number. i am an even number. i am greater than 3 × 7. i am less than 4 × 6. which number am i? (c) i am a two-digit number less than 80. i am even. my digits are the same. i am a multiple of 4. which number am i?​