B) (6 2/5⋅2 11/12-16)⋅2 1/4;

в) Выполним действия по порядку.

1. $$6\frac{2}{5} = \frac{6 \cdot 5 + 2}{5} = \frac{30+2}{5} = \frac{32}{5}$$
2. $$2\frac{11}{12} = \frac{2 \cdot 12 + 11}{12} = \frac{24+11}{12} = \frac{35}{12}$$
3. $$2\frac{1}{4} = \frac{2 \cdot 4 + 1}{4} = \frac{8+1}{4} = \frac{9}{4}$$
4. $$\frac{32}{5} \cdot \frac{35}{12} = \frac{32 \cdot 35}{5 \cdot 12} = \frac{8 \cdot 7}{1 \cdot 3} = \frac{56}{3}$$
5. $$\frac{56}{3} - 16 = \frac{56}{3} - \frac{16 \cdot 3}{1 \cdot 3} = \frac{56}{3} - \frac{48}{3} = \frac{56-48}{3} = \frac{8}{3}$$
6. $$\frac{8}{3} \cdot \frac{9}{4} = \frac{8 \cdot 9}{3 \cdot 4} = \frac{2 \cdot 3}{1 \cdot 1} = \frac{6}{1} = 6$$

Ответ: $$6$$