Where an employee performs work during his workweek, some of which
is exempt under one section of the Act, and the remainder of which is
exempt under another section or sections of the Act, the exemptions may
be combined. The employee's combination exemption is controlled in such
case by that exemption which is narrower in scope. For example, if part
of his work is exempt from both minimum wage and overtime compensation
under one section of the Act, and the rest is exempt only from the
overtime pay requirements under section 13(b)(6), the
employee is exempt that week from the overtime pay provisions but not
from the minimum wage requirements.