Final answer:
To calculate how far the Serenity and Mystic will be in 2 hours, we add the distances each will travel at their respective speeds. The Serenity will travel 26 miles, the Mystic will travel 42 miles, and together they will be 68 miles apart.
Step-by-step explanation:
The question involves calculating the distance two objects will be from each other after traveling at different speeds for a certain amount of time. The Serenity travels at 13 mph and the Mystic travels at 21 mph. To find how far apart they will be in 2 hours, we can use the formula: distance = speed × time.
For the Serenity: distance = 13 mph × 2 hours = 26 miles
For the Mystic: distance = 21 mph × 2 hours = 42 miles
To determine how far apart they will be, we simply add the distances because they are traveling in the same direction: total separation distance = 26 miles + 42 miles = 68 miles.
So, the correct answer is: B) 68 miles.