Hello from JustAnswer.
I am not sure what information you are asking, but the situation may be more complex than you anticipate.
There is not a single correct answer for the detection rate for these drugs, because the detection rate for the Soma and Klonopin will depend upon whether they do the correct test to look for those substances. But if you were honest about what drugs you had taken, then they should have obtained the proper test. And if you had taken both drugs that day, then the detection rate would be close to 100%.
If they only did a common drug screening test, it usually does not include a test for Soma. And the generic screening test for benzodiazepines will frequently miss the Klonopin. But that is why they should have obtained the test that would detect each of these drugs. If they order a GC/MS test, it will not only be able to identify the Soma and Klonopin, it will also be able to detect the levels of each drug. However, if they only test the urine, the level of the drugs in the urine typically is not sensitive enough to identify that someone has taken a higher dose of the drug. If they ordered tests on the blood, then the level of the drugs in the blood may be able to say that someone took more than a therapeutic amount of the drug, particularly if the test was done when the level is peaking in the blood.
If you have not taken the Percocet in two weeks, it will be well out of your system, and it would not be detected by any test.
Is this the information you are seeking?