A survey was conducted at a local ballroom dance studio asking 80 students if they had ever competed in the following dance categories: Smooth, Rhythm, Standard. The students could list multiple dance categories. Some surveyed had not competed in any categories. For example, the 14 at the bottom of the Venn Diagram means that 14 students did not compete in any dance categories. The results were then presented to the owner in the following Venn Diagram.

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Determine the following probabilities.
Write your answers as a fraction or as a decimal to 2 decimal places.

a) P(Smooth) =  
b) P(Rhythm and Standard) =  
c) P(Smooth or Standard) =  
d) P(Rhythm or Smooth) =  

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