Answer
a) 99 cm
b) 602 $cm^2$
Work Step by Step
(a) We know the equation for perimeter:
$$ P=2l + 2w $$
Thus:
$$ P = (2)(28\ cm) + (2)(21.5 \ cm) \\ P = 99 \ cm$$
(b) We know the following equation:
$$ A= w \times l$$
Thus,
$$ A= (21.5cm)(28cm) \\ A = 602 \ cm^2$$
