Approximately 2.81 × 1 0 21 electrons flow through the electric device when a current of 15.0 A is maintained for 30 seconds. This is calculated based on the charge carried by the current and the charge of a single electron. Overall, the total charge delivered in this duration is found to be 450 coulombs.
;
Unsteady gait is the symptom most likely associated with vertebrobasilar insufficiency, as it relates directly to balance and coordination issues stemming from brainstem dysfunction. Other options either relate more to anterior circulation problems or do not directly indicate this specific condition. It is important to recognize how blood flow deficiencies affect various neurological functions. ;