3) (1 Double stranded DNA must be associated with cations, usually Mg2+. Why? O To aid stabilize the base-pairing in the double-stranded DNA To detain the DNA strands from separating To defend the DNA ends from nucleases O To attenuate impute indisposition from the phosphoryl groups 4) (1 Which reaction(s) can arise externally violating the cooperate method of thermodynamics. (T 298K) 。&H=-84 kj mol-1 s-+1 25 J mol-1 K-1 。dH:-84 kj mol-1 s-, 1 25 J mol-1 K-1 。dH_ +84H mol-1 s-+1 25 J mol-1 K-1