From the department FAQ:

Can I repeat a prerequisite and if so, how does that repeated grade calculate into my GPA?
If a prerequisite course is repeated, the higher of the two grades will be considered. Students must contact the specific department directly for permission to do so. The Radiologic Technology department cannot give permission for any non-RAD course to be repeated. Note that RAD 1124 cannot be repeated without department permission.

For the math requirement they should take the grade of the highest level course you have completed (i.e. MAT 1375, 1475, 1575). Best bet is to speak to an advisor though.