If you have done ODSSEYWARE please help 1. Why does air have weight ?

2. Because everything has weight

3. The force of gravity acts on the air molecules' mass

4. The pressure of the air molecules colliding with each other gives them weight

5. Air fills its entire volume, producing weight

regulation of gene expression. gene expression can be regulated by various cellular processes with the aim to control the amount and nature of the expressed genes. these regulatory proteins bind to dna and send signals that indirectly control the rate of gene expression

explanation:

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