Answer:
- x = 7
- x = 11
- 5
Step-by-step explanation:




◇◇•◇◇





♤♤•♤♤



Answer: Our Cost function is discontinuous at every integer after x>10.
Step-by-step explanation:
Since we have given that
For the first 10 minutes , the service charges = $0.30
Let the number of additional minute be 't'.
Amount charge for each additional minute = $0.05
Using the greatest integer function:
So, Cost C of a call in terms of time 't' minutes would be

As we know that Greatest integer is discontinuous at every integer.
So, our Cost function is discontinuous at every integer after x>10.
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