Which graph represents an function?

What are the measures of ∠a, ∠b, ∠c and ∠d? explain how to find each of the angles. measure need asap

Asap i need it now choose all the answers that apply. sex-linked disorders affect males more than females affect females more than males can be carried by females, without being expressed are always expressed in males are caused by genes carried on the x and y chromosomes

Find the exact value of each of the following. in each case, show your work and explain the steps you take to find the value. (a) sin 17π/6 (b) tan 13π/4 (c) sec 11π/3