Can someone explain to me why these answers are incorrect? then explain the correct the answer?

Question 3. ¿Qué es un requisito para entrar el pre-kinder?

Answer 3: acta de nacimiento.

Explanation 3: Pre-kinder is a classroom-based preschool program for children below the age of five. To enter pre-kinder, it is necessary to prove age with a birth certificate.

Question 8: ¿Cómo puede producir menos contaminación del aire?

Answer 8: conduce menos.

Translation 8: How can you produce less air pollution? drive less.

Explanation 8: Motor vehicles pollute the air, and driving less reduces air pollution.

Question 12: ¿Qué NO es un saludo para una carta a la familia?

Answer 12: cordialmente

Translation 12: What is NOT a greeting for a letter to the family? Cordially

Explanation 12: cordially, it is used in business letters as a expression of courtesy and does not imply an expression of affection like the other expressions.  

the answer to the test is 1. b 2. d 3. a. 4. c 5. b 6. a 7. c 8. d 9. a 10. a 11. c 12. b 13. d 14. c 15. a 16. a 17. d 18.b 19. d 20. c 21. a 22. c 23. c.     24. a guateque canpesino is a family gathering brought to the countryside to celebrate harvest time. here at the gathering people sing, listen to music, play the gutair, laud, tres, guiro, dance. they also eat roar pork, rice, and beans. 25. yo soy alta means i am tall. the reason why this sentence uses the verb -see is because the characteristics that is being described is how someone is like.