How many cm long wooden strips do you need to make a cuboid frame? The length is 35cm, the width is 20cm, and the height is 20cm

Cuboid formula: (length + width + height) * 4
So: (35 + 20 + 20) * 4 = 75 * 4 = 300 cm

How to calculate the area of fan

Area of sector = area of circle (π × square of radius) × central angle of circle / 360 degrees
=Area of circle (π × square of radius) × radian / 2 π
=Square of radius × radian / 2

Who can tell me what is the formula of sector area? Friends, you can say it in detail

The area of the circle is π R & # 178;
So sector area = π R & # 178; * center angle / 360

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