A boat crosses a river from port 𝐴 to port 𝐵, which are just on the opposite side. The speed of the water is 𝑉𝑊 and that of boat is 𝑉𝐵 relative to still water. Assume 𝑉𝐵 = 2𝑉𝑊. What is the time taken by the boat, if It has to cross the river directly on the 𝐴𝐵 line

Question : A boat crosses a river from port 𝐴 to port 𝐵, which are just on the opposite side. The speed of the water is 𝑉𝑊 and that of boat is 𝑉𝐵 relative to still water. Assume 𝑉𝐵 = 2𝑉𝑊. What is the time taken by the boat, if It has to cross the river directly on the 𝐴𝐵 line

(A) $\dfrac{2D}{V_{B}\sqrt{3}}$

(B) $\dfrac{\sqrt{3}D}{2V_{B}}$

(C) $\dfrac{D}{V_{B}\sqrt{2}}$

(D) $\dfrac{D\sqrt{2}}{V_{B}}$