I don't understand this trigonometry question. This is the link of the picture:

$AC = 4$
$BD = 20$ (Bigger than $A C \times 5$ so $5 \times 4 = 20$)
Found: 
$BCD= 157.38^\circ$
$ABC \text{ or } ADC = 22.26^\circ$
Question:
Find the ratio between the length of the long diagonal of the rhombus volume.
What does that mean?
Thanks.
Correct answer is: 1:2.038 OR 0.4907

Hint:  You can evaluate the side of the rhombus from the Pythagorean theorem and the lengths of $BC,BE$ and you have the long diagonal is $BD=20$, so take the ratio.
