Affiliate Marketing Secrets

There’s so many rumors and half-truths about music on the radio. The biggest ones which I like answer to are:
1.Does record labels really pay radio station to play their Artist songs?
2.Do radio only play what’s in the Top 40?
3.Do people really still request songs in these days? Because why request a song when I have so many disposable options to listen to said song whenever I want?
YOU MUST WORK OR PREVIOUSLY WORKED IN THE RADIO INDUSTRY TO ANSWER! EX. RADIO DJs PRODUCERS ETC …