The reason fast food restaurants often are found in close proximity to each other is a. they enjoy competition b. location clustering near high traffic flows c. low cost d. availability of skilled labor e. all of the above

b. location clustering near high traffic flows

Explanation:

Proximity to customers is a major consideration when deciding on a business location.  A business situated in areas with many potential customers has a high probability of succeeding. Restaurants are usually strategically situated in places with heavy customer flow.  

Restaurants may be established near offices, in market places, near public transport terminus, or other location convenient to customers.  With time, customers tend to associate that particular building, area, or street with restaurants. As the area becomes synonymous with restaurants, more customers will visit it, leading to more restaurants to open in that locality.

answer(eu) is the correct answer;

the amount of money you earn by working is your income.

the percentage of people actively looking for a job is called unemployment.