learndash_get_activity_human_time_diff( int $activity_started, int $activity_completed, int $minimum_diff = 60 )
Calculate the human readable time spent on activity.
(int) (Required) The start timestamp to compare. Default 0.
(int) (Required) The completed timestamp to compare. Default 0.
(int) (Optional) The minimum difference between started and completed time.
Default value: 60
(string) The human readable time difference.