Below are two pictures from the electrical inspection course. In question is the clamp measurements on the conduit. One pic says every 3 feet, the other says every 5 - 6 feet. Which is it supposed to be? In Canada the CEC don’t have exact measurements like that. But to pass a InterNACHI quiz, what will they expect as the answer?
Good questions. The NEC wouldn’t require the supports attached to the structure to be installed as depicted in either graphic. Often mast services are required to meet the requirements of the specific utility company that will be connecting to it.
For example there are some utilities that have a minimum mast size for rigid metallic conduit of 2.5", so 2" would be too small. The NEC simply states the the mast need to be of adequate size to support the drop, no minimum sizes are given.
IMO another notable problem is the use of the words should. It’s either a requirment or it isn’t. If it’s required then shall is a more correct term.
It will be interesting to hear what the correct answer is for a test question.
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Well even if it’s incorrect that answer is in one section of the training material. The should also use the correct name for the raceway which is rigid metallic conduit or RMC. Plumbers run pipe. 
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No one does it like that anyway. You are at the gable end of the building and your going to put a hole through the roof and the soffit? In my neck of the woods the mast is simply attached to the end wall of the building. No holes, no flashing and the meter is on that end also.
Most houses in Maine have the conduit electrical masts going through the overhangs.
Very common here as well. Really depends on the clock position of the home compared to the pole.