Problem: How does the sentence end?

So 
Answer: Robert was confident because Randy forgot to study for the upcoming test and Robert studied.

Problem: How does the sentence end?

The man was more scared to take a plane than a bus because the 
Answer: plane traveled at a faster speed.

Problem: How does the sentence end?

Orchids are the favorite flowers of Randy but not Jason because 
Answer: Randy grew up around them as a child.

Problem: How does the sentence end?

The embassy could not withdraw the tourist's visa, but the consulate could, since the 
Answer:
embassy lacked the authority.