Different between open source software and licensed softwares?

Which of the following commands is more recommended while creating a bot?

In excel - calculate the actual increase/decrease from first quarter to the second quarter then subtract subtract first quarter value from second quarter total then divide result by first quarter value

Kenny works with an it company. his company is about to launch new software in the market. he has to ensure that this new software is functional and meets all of the quality standards set up at the planning stage. which job profile is kenny likely to have? kenny is likely to have the job profile of a blank .