The answer is A. <span>effective length of the tube
In wind instrument, the effective length is not the actual length of the instrument but only the length that the finger holes manage to cover.
The more holes it managed to cover, the higher frequency of vibration it might able to produce, which lead to higher pitch of the instrument.</span>
Answer:
The answer to your question is: Active transportation
Explanation:
Cell can move molecules in or out of it by two processes: Active or Passive transport.
Active transport: is the movement of molecules against a concentration gradient. Use proteins or enzymes to happen.
Passive transport: is the movement of molecules or ions from a higher concentration to a lower concentration.
Yes,oxygen-rich blood is carried through pulmonary arteries from the lungs to the heart.
