what the input and output variables and units are. Comments start either with an apostrophe $(\text{'})$ or the word REM. In this class, all functions and subroutines will have a comment, or points will be deducted. All variables need to be defined with their corresponding units. k$.$ Debugging Exercise. In the TestBHP subroutine, set a breakpoint on the line that obtains the surface pressure from the user. Click in the left margin next to the word SurfPressure $=.$ This sets a breakpoint. A red ball will appear on the line. Other than the lines dimensioning variables, breakpoints can be set on most lines. Press F$5$ to start the code running. The computer will stop at the first break point. Successively pressing F$8$ will execute line by line. Hovering your cursor over the variables will show you their contents. Remember, a yellow highlight indicates the current line of execution. The right$-$hand$-$side is ready to go$,$ while the left$-$hand$-$hand side is still at the old condition. l$.$ Submit a document with a cover page, graphs, tables and code. Also turn the Excel spreadsheet. m$.$ Bonus Challenge $(5$ points$).$ Create a new functi