Take a look at this plot:
It is very similar to the one you created in the previous exercise. In addition to the data, it shows a track called Genes with gene annotations. In what order would you execute the following code fragments to add this track to the plot?
plotTracks(list(ideogram, cover_track,peak_track, tx, GenomeAxisTrack()), chromosome="chr20", from = start_pos, to=end_pos)
tx <- AnnotationTrack(TxDb.Hsapiens.UCSC.hg19.knownGene, name="Genes")
tx <- GeneRegionTrack(TxDb.Hsapiens.UCSC.hg19.knownGene, name="Genes")