need help with IF formula - depending on which column has information entered.

Hi & Thanks in advance for your help!!

Attached is a copy of my excel spreadsheet. I have all the formulas worked out already but just added two new columns. I want to use the IF formula for columns H & I. The total is calculated in Column J. If there are any values entered in those columns, nothing should be entered in the "work/lunch" times/columns. Basically, either the employee has a work day or a fitting day. The IF formula would be in the K column. Regardless of what's entered in H & I, the minimum number of hours should be 1. After that, it should be calculated in 15 minute increments. The $/rates breakout I have listed in K13 - K19 would still apply. I hope I explained myself correctly but sorry if I didn't. Would be more than happy to answer any questions & appreciate all the help!!