That would be a union.
a riot is a sudden rash of violence against authority,property or people. a strike is a work stoppage caused by the mass refusal of employees to work.
lay-off, work stoppage
yes
That is the correct spelling of "stoppage" (cessation of an action).
A work stoppage in order to force an employer to respond to demands of the workers.
A strike or work stoppage.
The homophone for a stoppage for a time is "pause."
20% of them
strikes
This depends on what company the employees work for, if the organization is open, if the employees are able to work from home etc. Many companies have closed so as not to put their employees in danger.
100000 employees work at Voltaire Ltd