Answer:

1) 81

2) 17.415

3) 132.665

Step-by-step explanation:

1) (12 x 12) - (9 x 7) = 81

2) (9 x 9) - (3.14 x 4.5 x 4.5) = 17.415

3) (3.14 x 13 x 13 x 0.5) - (3.14 x 6.5 x 6.5) = 265.33 - 132.665 = 132.665

Kuya/ate yung #4 and #5 walang shaded region..