Poetry uses forms and conventions to suggest differential interpretation to words, or to evoke emotive responses. Devices such as assonance, alliteration, onomatopoeia and rhythm are sometimes used to achieve musical or incantatory effects.
The average speed of an object tells you the (average) rate at which it covers distance. If a car's average speed is 65 miles per hour, this means that the car's position will change (on the average) by 65 miles each hour.
To find average speed, divide the total number of miles traveled by the total elapsed time in hours. The answer is the average speed in miles per hour. For example, imagine a car traveled 90 miles in 1 1/2 hours. To determine the average speed, divide 90 by 1.5. The answer is 60 mph.