2 part answer
I'm having problems figuring a way to calculate on the table
Answer is don't store calculations. Rarely is it necessary and most of the time is ill advised.
2 - you'd need a numerical value associated with the text value. If being picked from a combo, the bound column would be number and the visible one "daily".
Back to #1 - you'd store the values and do the math on them in forms, reports or queries.
E.g. "full risk" control = Risk x Frequency x Impact, or
3 x 2 x 4 = 24 and choose the full risk assessment value that corresponds to 24 in your table. Note: 24 is not just a calculation but is associated with a risk factor text value in your table that corresponds to the form calculation.