Mr. Shiv is new to salesforce and he want to design a cron expressssion. Help him to desgin a cron expression using system.now() and desgin the cron by adding 20 min. in existing time and only for one...

Extracted text: Mr. Shiv is new to salesforce and he want to design a cron expressssion. Help him to desgin a cron expression using system.now() and desgin the cron by adding 20 min. in existing time and only for one time. Salesforce, Batch, Queueable, Schedular