17._____ convey rainwater from roof drains through a rainwater leader and into a storm sewer. a.Building storm drainsb.Waste stacksc.Leviesd.Main vents 18.Storm drain traps should be used when a roof drain body is located within _____’ of a storm door, window, or any other opening to a building. Completion: type the correct answer in the blank 1._____ provides circulation of air to or from a sanitary drainage system and also provides air circulation within the sanitary drainage piping to protect trap seals from siphonage or back pressure.2.A(n) _____ pipe is any pipe or fitting that makes an angle of less than 45° with the horizontal plane.3.A(n) _____drain is an drainage pipe extending horizontally from a soil or waste stack or building drain with or without vertical sections or branches4.A(n) _____ is any vertical line of soil, waste, or vent piping extending through one or more stories.5.A(n) _____ is a vertical length of stack at least 8’ high within which the horizontal branches from one story or floor of the building are connected to the stack.6.A(n) _____ is a combination of elbows or bends that brings one section of the pipe out of line but into a line parallel with the other section.7._____ is the slope of a horizontal run of pipe and is expressed as a fractional inch per foot lengthof pipe.8._____ refers to the various turn that may be required in drainage pipe.9.Sanitary drainage piping must be equipped with an adequate number of properly installed _____to allow easy access to the system if stoppage occurs.10._____ within the drainage system allows wastewater to flow freely through the pipes and also removes objectionable gases from the sanitary drainage system.11._____ is a common problem in drainage piping.12.A(n) _____ is the extension of a soil or waste stack above the highest horizontal drain connected to the stack.13._____ is the length of vent pipe measured along the centerline of the pipe and fittings.