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Thank you We sneak and here's your smoke Do sure

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try to sit up straight Just imagine you're a glam

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metal bands hair Consider the following class hierarchy Upward arrows

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indicate an inheritance relationship which of the following are correct

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And here the potential answers Yeah All right as the

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problem states up arrows indicated inheritance relationship and we already

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know that inheritance is just a big fancy word for

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is a relationship No fast song is a song slow

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song is a song too and we can go step

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further and say power ballad is a slow song which

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is a song Well we could extend this even further

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by saying november rain is a power ballad november rain

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than inherits any and all of the fields methods and

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nested classes from power ballad which inherits from slow song

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which inherits from song for exam song would contain members

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that are relevant all songs and every subclass of song

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things like are this name instruments song blank and so

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on things that every song will have Well november rain

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would be extremely specific like emotional axl rose vocal which

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is something out every single half aside from simply knowing

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their relationship between classes It's also important to know how

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to properly declare and create a variable setting it all

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up typically goes like this class variable named equals new

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glass for supplies Yeah right left side of the equation

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declares a variable to refer to An object song a

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for example lets the compiler know that you're going to

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use a to refer to data of the variety song

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but that object doesn't actually yet exist On the other

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side of the equation we get down and dirty and

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actually a sign an object to that variable A new

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power ballad for example would be created with song a

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equals new power valid All right the question is asking

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us which of these three option for declaring in creating

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variables are correct starting with option one song a equals

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new power balance and that's what we just did a

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second ago and it works too and song be equals

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New slow jam Yeah perfectly good way of creating a

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slow jam Another good way would involve candles rose petals

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and a saxophone solo But this is a little quicker

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option One is good Option two is a little weird

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It has as creating a slow song and power valid

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and having them equal new song and slow song objects

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but that's just not gonna fly the left side of

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the equation declares variables name and its class and the

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right side actually creates the object Option two is trying

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to declare a variable of the type that's a subclass

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of the actual object or creating that's like declaring that

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you're going to be dracula for halloween But he actually

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dress up some generic monster The option to option three

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works like option one declaring variables and b to be

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songs and then creates new fast song and slow song

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objects So yeah three work with options One of three

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working and to being wrong That makes the our answer

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