The major divisions in a play are called halves

acts

none of these

parts

the major division in a play are called acts.

"an enormous ornamental bat"

"carried on the arm"

"as the atmospheric conditions demanded"

Explanation:

These are the phrases from this sentence that create a comic tone. In this excerpt, the author wants to convey the idea of the umbrella being an object of pretentiousness, and not one that serves any purpose. He does so by using phrases that convey this idea, and that emphasize the uselessness of the umbrella.