Answer:
they tend to run more smoothly and on schedule;
not having a human on board to deal with unexpected problems
Explanation:
I just had the same one
The walls of veins have the same three layers as the arteries. Although all the layers are present, there is less smooth muscle and connective tissue. This makes the walls of veins thinner than those of arteries, which is related to the fact that blood in the veins has less pressure than in the arteries. Hope this helps. Have a nice day.
