I keep getting an Abort() Called error

I keep getting an Abort() Called error in the Circle() when I try to run the program after putting Text("25%") in. Any ideas! Sorry, I am new to Swift and programming in general.

 I try to run the program after putting Text("25%") in. Any ideas! 

No ! How could we guess where you put Text("25%") ???? Please show the code.

I keep getting an Abort() Called error
 
 
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