compound verb agreement

11. Margo and her parents ____
each other often

O visits
O visit

12. Neither Matt nor his brother ___
at the party

O was
O were

13. Either the worker or the boss the merchandise.

O delivers
O deliver

14. Sammy and her friends ___
at the mall,

O shops
O shop

15. the cows or the pigs___ in the barn
O lives
O live