Final answer:
The best representation for determining how many planes had an average cruising speed of 0.84 Mach is the table provided.
Step-by-step explanation:
The best representation for determining how many planes had an average cruising speed of 0.84 Mach is the table provided. The table lists the average cruising speeds of different planes and the number of planes with each speed. By looking at the number of planes with an average cruising speed of 0.84, we can determine the count.
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