What does the word "petulantly" mean as it is used in paragraph 10 of The Necklace?

To be petulant means to
be rude in one's speech or behavior, and it can describe someone who is marked by a temporary or
unpredictable irritability produced by something seemingly small or insignificant. In the story,
Madame Loisel is provoked by the invitation that her husband has procured to a fancy party from
the Minister of Education and his wife.

Monsieur Loisel expects his wife to
be delighted, as she is someone who has always felt that she was destined to enjoy all the
luxuries and prestige that life has to offer and that only the circumstances of her birth and
marriage have kept her from them. However, she is upset, and she flings the invitation across
the table "petulantly"in a childish way. She is not grateful for his efforts; rather,
she is irritated when she ought to be happy and unpredictably peevish when she ought to be
grateful.