Which of the following is a "Usability Metric" used to measure Efficiency during evaluation?

Question

Which of the following is a "Usability Metric" used to measure  Efficiency  during evaluation?

Answer

The time taken by a user to successfully complete a specific goal.

Answer

The number of errors a user makes while completing a task.

Answer

The percentage of users who expressed satisfaction with the colors.

Answer

The total number of downloads the application has on the App Store.

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