Which of the following is true regarding a dihybrid cross
1. is a hybrid cross multiplied by 2
2. animals or plants that differ in a single traits are crossed and the pattern of inheritance is observed to determine if the trait is passed on independently
3. None of these
4. animals or plants that differ in two traits are crossed and the pattern of inheritance is observed to determine if the two traits are passed on independently
5. animals or plants that differ in three traits are crossed and the pattern of inheritance is observed to determine correlations among the traits