To calculate the opportunity cost per unit of a good, you can divide the decrease in the quantity of the good that is forgone by the ____.

Movie  は なんですか。

Date　(Romantic)  は なんですか。

Magazine  は なんですか。

Today  は なんですか。

Which of the following is/are correct resonance structure(s) for the following cation? Choose all that apply. Adding in lone pairs and hydrogens can be helpful. 

Which of the following is/are correct resonance structure(s) for compound A? Choose all that apply. (It may help to add lone pairs and hydrogens)

Identify the Lewis base.

What is the common name of the following substituent?

What is the name of the following bicyclic structure?