Which five computer terms are being described below?

a A changeover method where the old system is stopped overnight and the new system is introduced straight away.

b A changeover method where the new system is introduced into one branch of a company and its performance assessed before being introduced in all the company's branches.

c Type of validation that checks whether or not the correct number of characters has been entered.

d Part of the system life cycle that considers data capture forms, file structures, validation and screen layouts.

e Software development technique where the program is broken down into smaller parts and each part is tested separately.