Answer
a) This can be ensured by following some specific norms that are intended to make the system as much human friendly as possible. Those norms or guidelines are:
Make sure that each report or output screen is having a concise, easily understandable title.
The data and information in reports and output screens should be arranged such that each section consists of related data and is identified by clear section heads.
Information in tabular form should have row and column heads or labels.
Information in charts, graphs should have proper and clear legend to identify each dataset.
Things such as special characters, computer jargon, program codes should be avoided on the output screens and reports.
Messages should be clear and brief.
Long reports should be summarized in the beginning and segmented with proper labeling.