$\"\"$

Radius (r) of the circle is given by 10 cm.

$\"\"$

$\"\"$ (Multiply each side by 2)

$\"\"$ (Substitute $\"\"$ )

$\"\"$ (Multiply: $\"\"$ ) $\"\"$

Find circumference (C) of the circle.

$\"\"$ (Apply circumference formula)

$\"\"$ (Substitute $\"\"$ )

$\"\"$ (Multiply)

$\"\"$ (Substitute $\"\"$ )

$\"\"$ (Multiply) $\"\"$

The value of the diameter $\"\"$ and circumference $\"\"$ .