Quiz in My Last Duchess

Quiz Examples in My Last Duchess:

Text of the Poem 2

" (since none puts by The curtain I have drawn for you, but I) ..."   (Text of the Poem)

What does the Duke's unusual way of displaying the portrait suggest about him?

"Who'd stoop to blame This sort of trifling?..."   (Text of the Poem)

What is the irony of this rhetorical question?