What is your D-Value at ... (position)?
What is the D-Value at ... (place or position) (at ... hours) for the ... millibar level?
Answer
My D-Value at ... (position) at ... (figures and units) height above the 1013.2 millibars datum is ... (D-Value figures and units) ... (specify plus or minus).
The D-Value at ... (place or position) at ... hours for the ... millibar level is (D-Value figures and units) ... (specify plus or minus).
Note.- When the true altitude (radio altitude) is greater than the pressure altitude PS (Plus) is used and when it is less MS (Minus) is used.