On the other hand, flatMap() creates a new stream that is not parallel by default, regardless of whether the underlying elements were parallel.
flatMap() is a new stream that is not parallel by default, even though its elements are parallel streams.
A. [55. 88] [55, 88]
B. [55. 88] [88, 55]
C. [88. 55] [55, 88]
D. [88. 55] [88, 55]
2. D. The answer needs to implement Map because you are dealing with key/value pairs per the unique string text. You can eliminate A, C, E, and F immediately. ArrayList and Vector are Lists. HashSet and TreeSet are Sets. Now it is between HashMap and TreeMap. Since the question talks about ordering, you need the TreeMap. Therefore, the answer is E.