wreck in minimum time?A pair of scuba divers wish to dive on a wreck that lies $0\mathrm{.}4$

$km$ off the shore from a point $0\mathrm{.}8km$ from their present

position. If they can walk carrying their gear at $5k\frac{m}{h}$ and

swim at $3k\frac{m}{h},$ what course should they follow to reach the

wreck in minimum time?