In this case, cold air is a smaller cup and warm air is a larger cup. So when the air is colder, the same amount of water vapor will produce a higher relative humidity than the same amount of water vapor in warmer air. This is because we have to consider the amount of water vapor relative to what the air can hold.
The sequence of bases in DNA operates as a true code in that it contains the information necessary to build a protein expressed in a four-letter alphabet of bases which is transcribed to mRNA and then translated to the twenty-amino-acid alphabet necessary to build the protein.
The important thing is the sequence of A, G, T and C in a DNA strand, because it's the order of those bases that contains the code of DNA. DNA will usually be in a double stranded form, with two long molecules coiled around each other. Creating RNA. The ultimate purpose of DNA encoding is to create proteins, but DNA doesn't make proteins directly.