Measure length of radius of a circle draw a circle the same center so that radius was a half of radius of this circle a circle of 8 centimeters Help Please make the drawing

Measure the radius of OHMS (for example, 5 cm turned out). Draw a circle with this radius, with the center in a point O. Izmer radius OK at the second circle (for example, 3 cm turned out). Draw the second circle with the same center O. The circle in a circle will turn out. One circle with a diameter of 5 cm (for example), and the second circle with a diameter of 3 cm (for example) and with the general center O. Radiuses need just to be measured by a ruler in the textbook.
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