[originaltext] (3)Los Angeles is about to become the largest American city

(3)Los Angeles is about to become the largest American city to raise its minimum wage to $ 15 an hour, an increase to be phased in over five years. The wage is more than twice the current minimum rate required by US law. Some business groups, however, say such increases will cost jobs.
    Protesters demanding a higher minimum wage have been rallying around the country, from New York to Phoenix.(4)Minimum-wage workers went to Los Angeles City Hall last week as council members considered the wage increase. It was given preliminary approval Wednesday and is expected to pass a final vote June 10.
    The measure will raise the minimum wage in regular increases starting next year, to reach $ 15 an hour by 2020. Workers for small businesses and nonprofit organizations will reach the $ 15 mark the following year.
3. What is the current minimum wage required by US law?
4. What happened in Los Angeles City Hall last week?