The following yields the expected results:
1. For cell H7 and down: =IF(A7="","",IF(OR(WEEKDAY(A7)=6,B7=M$2),0,MIN((G7-F7)*24,3.5)))
2. For cell I7 and down: =IF(A7="","",(G7-F7)*24-H7)
3. For cell K7 and down: =IF(A7="","",SUM(H7*M$3,I7*M$4))
Let us know if you have any questions.