Feeding multiple columns from one sheet into another while combining totals based 2 column

Ok, so I am a total amateur with Excel and I'm quite surprised that I've gotten as far as I have so far. Basically, I've created a time sheet that allows me to breakdown our employees tasks and the time allotted to each task. The tasks are in a drop down menu to be selected from. However, each task is also related to a specific project, which is also in a drop-down menu. Each task is alotted a percentage of time (i.e. 30%). Then that percentage is multiplied times the total cost per day to allocate the price/task of that day for that employee. So .30 x $261.40 = $78.42 for Selective Demolition (Task) for 1328 Republic (Project) for that particular day. Then I need to total all of the amounts on another sheet, since a task might be repeated for the same project multiple times. I'll need it to show the total spent on "selective demolition" for that week. I just want it to auto populate in another sheet so that I don't have to waste my time do the numbers manually. Trying to streamline some processes with this file.

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employee time sheets.xlsx


I attached a screenshot of the current sheet. Please help!