Does anybody know this? 1/2 divided by 4/7

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

Which expression is equivalent to the expression below? (6c^2 + 3c) / (-4c + 2) / (2c + 1) / (4c - 1)a. 3c(2c-1) / (2c + 1)b. -3c(2c-1)^2 / (2c + 1)^2c. 3cd. -3c(just took the test its d. -3c)

Which of the following are parts of a sphere