Answer
a) The RNA polymerase molecules are moving right to left.
b) The RNA transcripts are much shorter than the genes that code them because the RNA transcripts usually only carry information transcribed from one gene, which codes one protein. The genes that code them however, code all of the different types of RNA.
Work Step by Step
a) The RNA polymerase unwinds the DNA helix in front of it as it moves along the DNA strand. So the RNA would be larger in the back, because the unwound DNA helix would be in the back.
