Explanation:
3.
the circumference of a circle is
2×pi×r
r is the radius.
so, in our case
2×3.14×14 = 87.92 cm
so, she will need 88 squares.
4.
this shape is the combination of 2 basic shapes : 1 rectangle and 1 half-circle.
the area of a rectangle is
length × width.
the area of a circle is
pi×r²
so, the area of a half-circle is
pi×r²/2
remember, the diameter of a circle is 2×radius (or the radius is diameter/2).
so, in our case the area is
12×4 + 3.14×(4/2)²/2 = 48 + 3.14×2²/2 = 48 + 3.14×2 =
= 48 + 6.28 = 54.28 ft²
6.
this shape is the combination of 2 basic shapes : 1 rectangle and 1 right-angled triangle.
the area of a rectangle is
length × width.
the area of a triangle is
baseline × height / 2
in a right-angled triangle we can use the legs as baseline and height pair.
so, in our case the area is
5×7 + 3×4/2 = 35 + 3×2 = 35 + 6 = 41 m²
7.
you put the "X" at the correct spots.