Mathematics homework help

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Answer question #1 or #2. You may do both for extra credit. 
1a.  Give your own example of a real life piece-wise function. State what f(x) and x represents. (12 pts)
1b.  Calculate f(x) for two values of x. Explain what these results mean.  (12 pts)
1c.  Explain why it is necessary for this function to be defined piece-wise  (6 pts)
2a.  Give your own real life example of a one-to-one function. State what the domain and range values represents. (10 pts)
2b  Demonstrate how this function works using the domain,  and range. (5 pts)
2c. Explain what a one-to-one function is. (5 pts)
2d. Explain why this function is a one-to-one function (10 pts)