Tokyo shares opened sharply lower Monday as traders here cashed in on recent gains after plunges in the Wall Street despite a solid jobs report for March. At 9:15 a.m., the 225-issue Nikkei Stock Average plunged 210.36 points, or 1.40 percent, from Friday to 14,853.41. The broader Topix index of all First Section issues on the Tokyo Stock Exchange was down 14.44 points, or 1.19 percent, to 1, 201.45.