Answer
Robert's height is 2310 millimeters (mm). This is equivalent to 2.31 meters (m) or 7 feet 7 inches (ft in). The conversion from feet and inches to millimeters is as follows: 1 foot = 304.8 mm, and 1 inch = 25.4 mm. Therefore, 7 feet = 7 x 304.8 mm = 2134 mm, and 7 inches = 7 x 25.4 mm = 176 mm.