Cube (algebra) however, easy to show that most numbers are not perfect cubes because "all" perfect cubes must have digital root 1, 8 or 9. That is their values modulo 9 may be only −1, 1 and 0. Moreover, the digital root of any number's cube can be determined by the remainder the number gives when divided by 3: Every positive integer can be written as the sum of nine (or fewer) positive cubes. This upper limit of nine cubes cannot be reduced because, for example, 23 cannot be written as the sum of fewer than nine positive cubes: The equation has
Edmund Root as the first commanding officer of . In the 1940s, he headed the naval officer procurement program in Chicago, where he oversaw the area's initial WAVES program. Root served as Naval Governor of Guam from May 15, 1931 to June 21, 1933. Root caused controversy between the United States and Japanese governments in 1933 when he expelled 112 Japanese citizens from Guam after their residence permits expired. The Guam Museum opened during his term. The Edmund S. Root Agricultural School in Guam is named in his honor. Edmund Root Edmund Spence Root (December 27, 1881 – February 27, 1961) was