What is the Lebesgue measure of a following set?

Question

This might be trivial for some of you. Let $E$ be a set defined by $ E= \{(x,y): a<\frac{x}{y}<b, c<\frac{y}{x}<d \}$. What is the Lebesgue measure of this set. Measure should be an area. But I am having hard time visualizing this.

Thank you very much in advance.

Answer 1

Picture (in a case where $0 < a < b, 0 < c < d$):