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An ant is moving around a few food piece...

An ant is moving around a few food pieces of different shapes scattered on the floor. For which food-piece would the ant have to take a longer round? Remember, circumference of a circle can be obtained by using the expression `c=2pir,` where r is the radius of the circle.

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(a) Radius of the semicircle part=`(2.8/2)cm=1.4cm`
Perimeter of the circle= `2π`r
Perimeter of the semicircle =`pi r`
The perimeter of the food piece=`2.8cm+pi r`
`=2.8cm+(22/7xx1.4)cm`
`=5.8cmxx4.4cm`
`=10.2cm`
(b). Radius of semicircle part=`2.8/2=1.4cm`
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