What is the order of rotational symmetry for alphabet O

Determine if the function below is continuous. a. continuous b. not continuous, 1 hole c. not continuous, > 2 holes d. not continuous, 2 holes

Geometry in the diagram, ∠abc is a right angle. ∠dbc = 30°27'40". find the measure of ∠abd.

Let f(x) = 5/x and g(x)=2x2+5x. what two numbers are not in the domain of f o g