Time delayed email from a Google Form response

I have a Google form. Responses will come in over several days. Not all will occur at the same time. I need a scheduled email to send after X number of days for each response. Then after another X number of days another automatic email to the original respondent and so on. Those individuals will be on a 12 day email response campaign for a polling process. Total number of automatic emails sent over the 12 day period is approximately 7. Help please! Thank you in advance! Awesome site. I have learned much so far…