1. Lara went first, then Kara, then Sara, then Mara, and then Tara.

2. Mr Cooper is the doctor

3. 72 days

4. East

5. They are father, son and grandson

6. 120 degrees

7. George – turkey; Vic – chicken; John – ham
If Vic had the turkey, then statement 2, Vic did not have the chicken would also be true. As only one statement is true, Vic did not have the turkey
Now assume John had the turkey sandwich. If so, the both the third and the fourth statements would be true which again contradicts the fact that only one of the statements is true. So John could not have had the turkey sandwich. So if Vic did not have the turkey and if John did not have the turkey, it must have been George
Now assume that Vic had the ham sandwich. This would then mean both the second and the fourth statements were true which is not possible. So Vic must have had the chicken.
The third statement (John did not have the chicken sandwich) is the only true statement.

8. Shape D

9. Blue, yellow, black, red, green

10. 10 of diamonds, King of Hearts, 8 of Spades