Yes, they should.
Anything other then urine.
Urine shouldn't be grey; it should be clear to yellow, depending. If your urine is the wrong color, or has a strong odor, you should consult your doctor.
Gas cylinders should be re-tested every 5 to 10 years, depending on the type of gas and the regulations in your specific location. It is important to have cylinders inspected regularly to ensure they are safe for use.
it should be around 180
For a healthy person, urine should be clear and odorless. If you are experiencing cloudy or white urine, you should seek medical attention by your family physician.
you shouldnt have to use a friends urine
No. Normal urine should be sterile.
I'm pretty sure your urine should smell like urine. Why are you smelling your urine?
why should you add 8 drops of urine in the Benedicts test
Upright
No - have you checked that it is firing on all cylinders - Sounds like the engine is mis firing or not firing on all cylinders.