Need marketing help with 3 intro questions (100-150 word response each)

Post a response of 100-150 words that addresses the following questions:

1. Which part of the marketing mix do you think has changed the most in recent years and why?
2. Which of the elements do you believe presents the biggest challenges to modern day marketers?
   Your answers should contain citation(s) from the text or another source(s) supporting your assertions.
3. Give examples of successful marketing strategies and explain why they work.

Respond to TWO of your peers’ post with responses of at least 50 words for each peer response.