It looks like you've uploaded a worksheet for "Differential Leveling" from a surveying final exam. Let's go through the content step by step:

The table is used for differential leveling calculations, showing data for various stations (STA). The columns represent:

• STA: Station names (BM-1, TP-1, TP-2, etc.).
• + (Plus readings): Backsight readings (BS).
• H.I.: Height of Instrument.
• – (Minus readings): Foresight readings (FS).
• ROD: Rod reading at each station.
• ELEV: Elevation of the benchmark or station (in feet or meters, based on the context).

Process to Solve for Missing Elevations:

To calculate missing elevations at each station, you can follow these steps:

1. Calculate H.I. (Height of Instrument):

   • $H.I. = Elevation + BS (\text{Backsight Reading})$
   • For BM-1, we have the initial elevation $4621.88$ and BS $3.94$: $H.I. = 4621.88 + 3.94 = 4625.82$

2. Calculate Elevation for each subsequent station:

   • $Elevation = H.I. - FS (\text{Foresight Reading})$

Let's go through each step to fill in missing values.

Would you like me to proceed with the detailed calculation for all the stations? Let me know!

Related Questions:

1. How is differential leveling different from profile leveling?
2. What are some common sources of errors in differential leveling?
3. How would you handle leveling over long distances?
4. Can you explain the role of turning points (TP) in the leveling process?
5. How do you choose the locations for benchmarks in surveying?

Tip: Always double-check rod readings and notes during a leveling survey to avoid computation errors later!