(a) The workweek is to be taken as the standard in determining the applicability of the Act. Thus, if in any workweek an employee is engaged in both covered and noncovered work he is entitled to both the wage and hours benefits of the Act for all the time worked in that week, unless exempted therefrom by some specific provision of the Act. The proportion of his time spent by the employee in each type of work is not material. If he spends any part of the workweek in covered work he will be considered