Q--Did breakdancing grow in popularity during WW2?
A--My step-by-step reasoning: Breakdancing was created by the African American youth in the early 1970s. World War II was a global war that lasted from 1939 to 1945.
So, the answer is no.

Q--Was Harry Potter and the Philosopher's Stone popular during the great depression?
A--My step-by-step reasoning: The Great Depression started in 1929 and ended in 1933. Harry Potter and the Philosopher's Stone was first published in 1997.
So, the answer is no.

Q--Did Thomas Greenhill's parents violate the concept of monogamy?
A--My step-by-step reasoning: Thomas Greenhill was a surgeon born to William and Elizabeth Greenhill. William and Elizabeth Greenhill had 39 children. Monogamy is a committed relationship between two people where usually they remain together for life. Thomas Greenhill was the last of his parents 39 children and was born shortly after his father died.
So, the answer is no.

Q--Would a Gray Whale fit easily in an above ground pool?
A--
My step-by-step reasoning: Gray whales are, on average, 39ft long. The average above ground pool is 10-33ft in diameter.
So, the answer is no.