Answer:
Natural:
b.A diamond company that owns nearly all of the world's diamond mines.
d.A soda company that spends over $3 billion on advertising every year.
e.A waste-treatment plant that cost a lot to build even though it costs only two cents to treat each gallon of waste.
Government
a.A small-town bar that is the only establishment in the county licensed to serve liquor.
c. A pharmaceutical company receives a patent for a new cancer-fighting drug.
Step-by-step explanation:
Government barriers are licenses or patents that prevent future firms from entering, natural is everything else.