Question

define frequency
and the area of circle​

Answer 1

Frequency is the number of occurrences of a repeating event per unit of time. It is also referred to as temporal frequency, which emphasizes the contrast to spatial frequency and angular frequency. Frequency is measured in hertz which is equal to one occurrence of a repeating event per second

Area of circle

A=πr2

Answer 2

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Frequency is the number of occurrences of a repeating event per unit of time. It is also referred to as temporal frequency, which emphasizes the contrast to spatial frequency and angular frequency. Frequency is measured in hertz which is equal to one occurrence of a repeating event per second.

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The area enclosed by a circle of radius r is πr². Here the Greek letter π represents the constant ratio of the circumference of any circle to its diameter, approximately equal to 3.14159.

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⠀⠀⠀⠀⠀ A = π r²