Question

1. the circumference of a circle with radius 7 cm is * 1 point

a. 44 cm
b. 21 cm
c. 14 cm
d. 49 cm

1. the perimeter of a rectangle with length 8 cm and width 5 cm is: * 1 point

a. 26 cm
b. 30 cm
c. 40 cm
d. 20 cm

Explanation:

Step1: Recall circle - circumference formula

The formula for the circumference of a circle is $C = 2\pi r$, where $r$ is the radius. Given $r = 7$ cm and taking $\pi=\frac{22}{7}$.
$C=2\times\frac{22}{7}\times7$

Step2: Calculate the circumference

$C = 2\times22=44$ cm

Step3: Recall rectangle - perimeter formula

The formula for the perimeter of a rectangle is $P=2(l + w)$, where $l$ is the length and $w$ is the width. Given $l = 8$ cm and $w = 5$ cm.
$P=2(8 + 5)$

Step4: Calculate the perimeter

$P=2\times13 = 26$ cm

Answer:

1. A. 44 cm
2. A. 26 cm