We have,
Length of the trunk = 3m = 300 cm
Circumference of trunk of tree = 176 cm
2πr = 176
2 × 22/7 × r = 176
r = 176×7 / 2×22
= 28cm
Radius = 28cm
∴ Volume of timber can be obtained from trunk of tree = πr2h
= 22/7 × 28 × 28 × 300
= 7392 cm3
= 0.74 m3