The combination of exempt work under sections 13(a)(5) and 13(b)(4), or one of these sections with exempt work under another section of the Act, is permitted. Where a part of an employee's covered work in a workweek is exempt under section 13(a)(5) and the remainder is exempt under another section which grants an exemption from the minimum wage and overtime provisions of the Act, the wage and hours requirements are not applicable. If the scope of the exemption is not the same, however, the exemption applicable to the employee is that provided by whichever exemption provision is more limited in scope unless, of course, the time spent in performing work which is nonexempt under the broader exemption is not substantial. For example, an employee may devote part of his workweek to work within section 13(b)(4) and the remainder to work exempt from both the minimum wage and overtime requirements under another section of the Act. In such a case he must receive the minimum wage but is not required to receive time and one-half for his overtime work during that week (C.F. Mitchell v. Myrtle Grove Packing Co., 350 U.S. 891; Tobin v. Blue Channel Corp., 198 F. 2d 245). Each activity is tested separately under the applicable exemption as though it were the sole activity of the employee for the whole workweek in question. Unless the employee meets all the requirements of each exemption a combination exemption would not be available.