Answer: Hot air is less dense than cool air; the heated air causes the balloon to rise simply because it is lighter than an equal volume of cold air. Buoyancy is an upward force that the air exerts, and it helps hot-air balloons and blimps stay in the air. A hot air balloon uses a burner to heat up the air inside the balloon.
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Answer:
the answer for your question is 3 and 4
Polygenic inheritance is determined by multiple Genes <span>located at different loci on different chromosomes.
Polygenic inheritance happens when an individual posses quantitative traits that become a variation compared to the parent's traits.
This phenomenon happens due to the combination of two or more genes that resulted in the characteristics that considered as the combination of both parents' characteristic.
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