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6. in the dna double helix, how are the two strands of dna held together? a. chemical bonds between base pairs hold the two strands of dna together. b. hydrogen bonds between the base pairs hold the two strands of dna together. c. hydrogen bonds between sugar groups and phosphate groups hold the two strands of dna together. d. chemical bonds between sugar groups and phosphate groups hold the two strands of dna together.

You need to make 500ml of 7h9(+) media with 1x adn and 30ug/ml of the antibiotic kanamycin. your stock solutions are 10x adn and 30mg/ml of kanamycin. the solvent is distilled water. how much of each component will you need to make the desired final solution?

What is the primary goal of human communities?