83. A log with a nail in the middle was left in the cargo area of a truck. The log rolled freely during movement and scratched the bottom. Which part of the cargo area could be damaged? Dimensions of the cargo area: $3 \times 2$ m; length of the log 2 m.
83. Four semicircles with a radius of 1, centered at the vertices of the rectangle, will not be damaged. The remaining areas of the body, with a total area of $6-\pi$, may be damaged. They constitute $1-\frac{\pi}{6}$ of the body.