6561, 81, 9, ____?
3 \( \frac{1}{2} \)
3
4 \( \frac{1}{2} \)
4
B. 3
6.4 × 3.8 × 4.2 × 0.3 =
30.6432
72.0192
00.0192
None of the above
A. 30.6432