If you count the tires on a large tractor-trailer that is unloading food at your local supermarket, you may be surprised to count 18 tires. Why so many tires?
a. Because large tractor-trailers require extra tires for added support and stability
b. Because some tractor-trailers have multiple trailers attached, each needing their own set of tires
c. Because having a greater number of tires helps distribute the weight of the heavy load more evenly
d. Because larger tires are needed to handle the weight and stress of heavy loads
e. Because having more tires decreases the likelihood of a blowout and improves safety on the road