Where to view the ratio of actual costs to estimated costs for a task?

How to close a task? How to delete a task? How to rename a task? How to change task parameters? How to view task activity? How to view the task event history (log)? How to find out if the assignee has opened their task? How to open the task menu? What actions are available in the task menu? How to change the task assignee? Who receives notifications about task events? How to change the subscriber list? How to bookmark a task? How to manually log time and financial costs in a task? How to expand the task window to full screen? How to change the estimated costs of a task? How can I delete an event record from a task? How can I see how long a task remained in a specific status? How can I repeat a task with subtasks? How can I close a task retroactively? How do I copy a task? How do I move a task? How do I reopen a completed task?