Assume in a real business setting you want to know if spending more money on marketing increases sales. How do you appro

[answerhappygod]

Assume in a real business setting you want to know if spending
more money on marketing increases sales. How do you approach this
task? Also assume you want to have an estimate of the volume of the
sales increase as a function of the money you spend on marketing.
Explain how you would do this task. What data would you need to
collect and what assumptions would you need to make?
PLEASE PROVIDE VALID RESULT