Paramterized SSIS Sql query in "Execute SQL Task" and Send Email

I am writing down an SSIS package which will be running after every 30 minutes. I am stuck at and one of the requirement is
1) Write SQL query
2) Get the data for last 30 minutes (Average of some data)
3) Send a mail if the average value is more than some threshold

I have written a specific query where I am giving hardcoded Datetime and getting the result and sending out the mail.

I would like this SQL query to be parameterized so that it takes DateTime as parameters ?

Thanks