I would be very grateful if someone provided me some hints to tackle this problem:
A human gene with 4 exons and 3 introns has been identified.
Introns have 456, 1500, 224 and 524 pairs of nucleotides respectively.
Exons have 2300, 500 and 4600 pairs of nucleotides respectively.
When performing a Northern Blot with a RNA probe for this gene in a human cellular extract,a pattern with 3 bands was observed in the autoradiography:
Each band corresponds to RNAm molecules of the following sizes: approximately 2700 pairs of nucleotides, 1200 pairs of nucleotides