Which of the following statements regarding workers' compensation insurance is true?
1) Employers who file the most claims pay the lowest premiums on the insurance coverage.
2) Employees are required to bear half of the entire cost of workers' compensation insurance.
3) Workers' compensation insurance includes only rehabilitation expenses.
4) The federal government is responsible for workers' compensation legislation and regulation.
5) Workers' compensation insurance compensates workers who are injured on the job or become ill through work-related causes.