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# The area of the ring with radii 10 and 20 equal to -942.45

a: The area of the ring with radii 10 and 20 equal to -942.45

A ring is a flat geometric shape bounded by two concentric circles.

Ring area formula
where R is the radius of the outer circle, r is the radius of the inner circle.

Solution:

S = π·(R^{2}-r^{2})

= π·(10^{2}-20^{2})

= π·(100-400)

= -300π

=

-942.45

a: The area of the ring with radii 10 and 20 equal to -942.45