#### A road roller (in the shape of a cylinder) has a diameter 0.7 m and its width is 1.2 m. Find the least number of revolutions that the roller must make in order to level a playground of size 120 m by 44 m.

**Solution:**

#### If the volume of a cylinder of height 7 cm is 448 π cm^{3}, find its lateral surface area and total surface area.

**Solution:**

**More Solutions:**

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