Final answer:
The given statement is false; tasks completed one after another are called sequential tasks, not concurrent tasks, which occur simultaneously or overlap in execution.
Step-by-step explanation:
The statement 'When tasks must be completed one after another, they are called concurrent tasks.' is false. Tasks that must be completed one after another are referred to as sequential tasks or serial tasks, as they occur in a series or sequence. In contrast, concurrent tasks are processes that occur at the same time or overlap in execution.
For example, learning a foreign language involves performing multiple tasks which can sometimes happen simultaneously, similar to riding a bicycle where you must balance, pedal, and steer all at once. But this comparison to concurrent tasks only applies in a metaphorical sense, as the cognitive processes may seem to overlap but are not concurrent in the technical sense.
Concurrent tasks would be like a computer processing multiple instructions at the same time, or a chef cooking several dishes at once, where each dish requires attention and activity at overlapping times. The sum of the time it takes to complete concurrent tasks is not just the total of individual task durations because they are happening in parallel.