The air in the room became TENSE right before the big debate began, making everyone feel nervous and quiet.
Anxious or strained
To get the best results, the chef made sure the oven temperature was OPTIMAL for baking the cookies, not too hot and not too cold.
Best, ideal
The park had NUMEROUS kinds of flowers - dozens of roses, tulips and daisies - making it impoxxible to count them all.
Great in number; many