Let's carefully look at the sentence and understand how to complete it properly:
"The temperature was [tex]$110^{\circ} F$[/tex] on the hottest day of the [tex]$\square$[/tex] it only reached [tex]$99^{\circ} F$[/tex] the next day."
We need to fill the blank with the right word to make the sentence coherent and meaningful.
1. The structure of the sentence suggests that we are referring to the hottest day of a specific time period, and the context implies a temporal frame such as a season.
The correct way to write it should ensure clarity and proper grammatical structure. The result can best be placed as:
"The temperature was [tex]$110^{\circ} F$[/tex] on the hottest day of the season. It only reached [tex]$99^{\circ} F$[/tex] the next day."
Therefore, the correct word to fill in the blank is "season".
