Explanation:
An application interface or user interface ,is the set of features an application provides so that user may supply input to and recieve output from,the program.
You'll need a helper variable for this, so depending on your programming language, the solution becomes:
int helper;
helper = arr[i];
arr[i] = arr[j];
arr[j] = helper;
<span>D. Make changes to your code
Variables allow the ability to easily substitute numbers for other numbers.
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