Lookup 2 cell headers one one sheet to find answer on another

Hello,

I am trying to lookup the employee name and week # included on sheet A on sheet B in order to find the % of utilization during that week. The employee name is included in column A on sheet B and the week# is in Column B on sheet A and a header across 6 columns in sheet B. Here is an example.
How do I get the result that in Week 6, J Smith's percentage was 55%?

Spreadsheet A
A B C
1 Name Week # Total Hours
2 J Smith Week 5 25 Hrs
3 J Smith Week 6 22 Hrs
4 J Smith Week 7 15 Hrs

Sheet B
A B C D
Name Week 5 Week 6 Week 7
1 J Smith 10% 55% 42%


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