The correct answer would be that they have more MASS per volume than air.
Yes, because the balloon with air has a greater density than the empty balloon.Because there is a higher density in one balloon then the weight of the balloon will change
The specific proteins produced by cell B in response to the foreign substance are antibodies.
<h3>What are antibodies?</h3>
Antibodies are specific proteins produced by the immune cells of the body in response to a foreign substance called antigen which produces the immune response.
Antibodies are released by immune cells such as B cells.
The antibodies bind to antigen and tag them for destruction by phagocytes.
Therefore, cell B will produce antibodies.
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