Which of the following dienophiles will react the fastest with $1,3-$butadiene? Completely fill the bubble

corresponding to your answer.

Which two of the following reactants will yield the product shown in the box below? Completely fill the

two bubbles corresponding to your answers.

Which of the following is the major product of the Diels$-$Alder reaction shown below? Completely fill the

bubble corresponding to your answer.