What improvement most dramatically increased the speed and lowered the expense of commerce in the first half of the 19th century?

back in the area of iowa even though you were found in florida there is a system that they dont want to tell you about where they can go fish for you in other states and bring you back to be tried in front of the crime scene so your location

plz mark brainliest i would appreciate it btw i live in michigan too xd

the answer is b hope that