**Diameter of semi circle = 2 * (radius / 2**),

Suppose we have a semicircle, whose radius is 7 inch, then-

Diameter of the semicircle = 2 * (7 / 2),

= 7 inch.

So, diameter of the semicircle is 7 inch, whose radius is 7 inch.

**Area of semicircles = π * (r / 2) * (r / 2)**,

Suppose we have a semicircle, whose Diameter is 24 inch, then,

Now first of all, we calculate radius of given semicircle is–

**Radius = (diameter / 2)**,

Radius = (24 / 2) = 12 inch,

So, radius of given semicircle is 6 meter, now we use following area of semicircle formula for evaluating area of semicircle –

Area of semicircles = π * (r / 2) * (r / 2),

= 3.14 * 6 * 6,

= 113.04.

Therefore area of semicircle is 113.04 inch

^{2}, whose diameter is 24 inch.

**Circumference of semicircle = 2 * π * (r / 2)**,

Suppose we have a semicircle, whose radius is 7 inch, then we apply circumference of semicircle formula for evaluating circumference of semicircle –

Circumference of semicircle = 2 * π * (r / 2),

= 2 * 3.14 * (7 / 2),

= 21.98.

So, circumference of semicircle is 21.98, whose radius is equal to 7 inch.

For evaluating the Arc Length of semicircle, we use following formula–

Arc length of semi circle (s) = (radius / 2) * central angle,

Suppose we have a semi circle, whose radius is 7 inches and central angle is 60 degree, then –

Arc length of semi circle (s) = (radius / 2) * central angle,

= (7 / 2) * (π/180 * 60)

= 3.5 * π/3,

= 3.5 * 1.04,

= 3.64 inch.

So, arc length of a semi circle is 3.64 inch, whose radius is 7 inches and central angle is 60 degree.