Positive selection of t cells occur in .the thymus
The answer is smoke in air because air cannot be separated by filtration. Distillation deals with the conversion from gas to liquid. I believe that will work with smoke and air. Hope I helped. Goodluck
Answer:
Polar bears consume ringed seals (which are tertiary consumers) as well as fish like trout, salmon, and cod (which are secondary consumers).
Explanation:
Hope this helped.
Answer: Im not completely sure but I believe that is true as they do soemthing similiar in other types of surgeries.
Answer:
C or D. Success. Good bye.
