[Borek]

I've stated more than once that I assumed that different direction meant different sign

You never stated that. All your posts so far contained positive numbers only, so we assume that's one of the reasons you don't get correct answers.

We are wasting time now on discussion of what you did and what we did. What about getting back to the starting point - show what you did and what results that you have put into the system were flagged wrong. If not for any other reason, we will be able to compare them with our own calculations. Now we can't do even that, so we can't be sure what is wrong.

[Babcock_Hall]

If they were identical they would be not enantiomers.

They are mirror reflections, so they rotate polarized light by exactly the same amount - but in different directions. Say, for some solution of D OR is 22 degrees - then equivalent solution of L will have OR of -22 degrees.

Can you think of a way of expressing this difference between L and D in terms of their SR values?

Trish,

This is a key point.  Enantiomers rotate plane polarized light equally in magnitude but in opposite directions, all else held equal.  From this idea, one of the answers becomes trivial.

[Dan]

I've told you everything I've done.

OK, let me explain with an example. We want to see your working.

If you are given the question: what is the sum of 2 and 3?

We want to see this:

"I did the following calculation: 2 + 3 = 5"  this is showing your working.

Not:

"I plugged the numbers in and got 5"

The reason is that if you say:

"I plugged the numbers in and got 6", we have no idea where you went wrong.

If you said:

"I did the following calculation: 2 x 3 = 6", we can immediately see where you went wrong (you calculated the product instead of the sum).

Do you understand now why we keep asking you to show your calculations?