Cold and salty deep ocean water a) rises and mixes with freshwater b) is lighter than warm surface water c) sinks further as salinity levels decreases d) is more dense than warm surface water

oxygen +1 most likely

the dna molecules have a negative charge because of the phosphate groups in their sugar-phosphate backbone, so they start moving through the matrix of the gel towards the positive pole. power is turned on and dna fragments migrate through gel (towards the positive electrode).

explanation:

its temperature is increasing. this causes molecular vibrations to increase.