Please help I do not understand

Answer:
h = v × 3/B
[tex]h = 18 \: cm[/tex]
Step-by-step explanation:
[tex]v = \frac{1}{3} Bh \\ \\ h = v \div \frac{1}{3} B \\ \\ h = v \times \frac{3}{B} \\ \\ h = 216 \times \frac{3}{36} \\ \\ h = 18 \: cm[/tex]
I hope I helped you^_^