Which best describes how the government enables government monopolies to exist? by issuing a patent by allowing natural monopolies to exist by creating and running a monopoly by owning the means of production

The answer is "By owning the means of production". This is a common practice amongst governments. For example, in a lot of countries, governments have had monopolies on public utilities, telecom or railroads industries.

Answer "By issuing a patent" is not correct since a monopoly doesn´t rely on a single patent, it depends on an industry, a company, which develops many products and, by that logic, a lot of patents.

Answer "By allowing natural monopolies to exist" could also be correct, since sometimes there have been cases of privatization of already existing monopolies, but it is not such a common case as with owning the means of production.

Answer "By creating and running a monopoly" is also not correct, since it would be a waste of time and resources for the government when they can just own the means of production.

The correct answer on E2020 is

the underground railroad (apocope of the metropolitan railroad) is a system of urban trains located within a city and its metropolitan area. it is characterized for being a massive transport of passengers in the big cities, uniting diverse zones and their environs, with high capacity and frequency and in segregated form to other systems of transport. metropolitan railroads are built underground or on the surface, although most systems use mixed models where sections are combined in both modalities.

1 - as a result, the metro tends to reduce car travel for two reasons: first, due to the greater transfer of users from the car and, second, due to the reduction in the acquisition of cars in homes located in sectors near the stations of the metro.

2 -the metro allows to contribute effectively to the achievement of all the objectives of an urban development policy: it improves the efficiency of the city's economy by reducing travel costs and also generates a higher level of activities in the city center, taking advantage of of the agglomeration economies.

3 -it is a clean means of transport, since it uses renewable energy (usually electricity), taking care of the environment and avoiding excessive pollution.

offline recommendation systems option b

because recommendation systems produce a list of two ways

1. through collaborative filtering

or

2. through content-based filtering