The document you have uploaded appears to contain text and diagrams related to the interference of light, specifically in the context of Young's double-slit experiment. It discusses constructive and destructive interference patterns, along with the formulas used to calculate fringe positions.

Based on what I can see from the image, it looks like there are explanations and equations for calculating interference conditions, as well as diagrams showing wave patterns.

Could you clarify which specific "troues" (blanks) you want to complete, or if there are certain sections you would like more help with? This would help me provide more targeted assistance. Feel free to indicate which parts need completion or additional explanation.