What holds the two strands of a dna molecule together?

weak hydrogen bonds

hope that's right :)

the transfer for conduction is the heat transfering from the liquid to the spoon

the transfer for convection is the heat rising from the liquid to the air

the transfer for radiation is the heat going through the sides of the cup and to the air

at least that is what i would do

not sure if this is what you'r looking for nnew= nold