Step-by-step explanation:
a) here,
diametre = 19 cm
Area = ?
Now,
Area = pie d
= 22/7 *19
59.71 cm2
Therefore, area = 59.71 sq.cm.
b)
here,
Area = 1000 sq.cm
diametre = ?
Now ,
Area = pie d
1000 = 22/7 *d
7000 = 22 * d ( cross multiply between 7&1000)
7000/22 = d
318.18 = d
Therefore, diametre = 318.18 cm .