This item can be answered by the concept of ratio and proportion. The ratio of the sculpture's height and shadow should be proportional or equal to that of the person. Mathematically,
6 ft / 2 ft = h / 4 ft
The value of h in the equation is 12 ft.
5280 feet = 1 mile
5280 × 60 = 316800
316800 feet per hour
3600 seconds = 1 hour
316800 feet per 3600 seconds
316800 ÷ 3600 = 88
88 feet per second
