Simplify (1-cosΘ)(1+cosΘ) / (1-sinΘ)/(1+sinΘ)?

Which pair of angles are vertical angles? ∠1 and ∠4∠1 and ∠2∠2 and ∠4∠2 and ∠3more than one answer.

Arestaurant offers a $12 dinner special that has 5 choices for an appetizer, 12 choices for an entrée, and 4 choices for a dessert. how many different meals are available when you select an appetizer, an entrée, and a dessert? a meal can be chosen in nothing ways. (type a whole number.)

Which table shows a proportional relationship between miles traveled and gas used?