Answer:
A. Tissue
Explanation:
The cells join together to form tissues. So, option (A) is the correct answer.
Answer:
Radio frequency is short for RF, which is a kind of high frequency alternating current electromagnetic wave with frequency range from 3k hz-3k GHz
Because the frequency is high, so the molecular movement speed is fast, and the physical explanation of the heat of the object 100 is its internal molecular movement speed, the use of radio frequency energy to make the molecular high speed movement of course will achieve the purpose of heating
The correct answer is option B, that is, functional group.
A functional group refers to a part of a molecule, which is a classified/recognizable group of bound atoms. The functional group provides the molecule with its characteristics, in spite of what molecule comprises it, they are the centers of chemical reactivity. The functional groups in a molecule require to be determined when naming.
Respiratory system and the cardiovascular system
