<span>A Before the family left for the summer, Susan made sure her kids watered their plants, packed their bags, and cleaned their rooms.</span>
Just watch this video it will help https://www.khanacademy.org/math/algebra/introduction-to-algebra/alg1-manipulating-expressions/v/combining-like-terms-and-the-distributive-property
I think the answer is B, Blake reveals emotions being cultivated like a garden.
D, as the story's background is too familiar and as a structured plot, their differences would make up for each others and create attraction.
As far as i recall it is because the mixture and type of gases they attempted to use were more or less futile to sustain a air balloon to successfully travel and a medium rate of speed, and were over-encumbering and heavy.