In the absence of a route leading from seaward，the conventional direction of buoyage generally follows（）.

When steering a tow downstream around the shape of a sand bar，and staying on the proper side of the buoys，an operator should be cautious of（）.

（）is not a type of IALA maritime buoyage system.

The approach to the roads and harbor from the（）entails no difficulty.

Which nautical charts are intended for coastwise navigation outside of outlying reefs and shoals（）.

Which effect does speed through the water have on a vessel which is underway in shallow water （）.

A sailing vessel shall not impede the safe passage of a（）．

You are running parallel to the coast and estimate that the current is against you.In plotting a running fix using bearings from the same object on the coast，the greatest safety margin from inshore dangers will result if what speed is used to determine（）.

You are making tow.A loaded，open-hopper barge with independent tanks has placards，with alternating red and white quadrants，located at each side and end.You inspect the barge and find slight traces of water in the wing voids due to condensation.What（）.

You are entering an east coast port and see a buoy with a yellow triangle painted on it.This indicates（）.