How can I have a task start when a primary task ends. I mean like this -

--8<---------------cut here---------------start------------->8---
* TODO task a - fill the rubbish bag
* TODO task b - put rubbish bag into the bin outside.
--8<---------------cut here---------------end--------------->8---

So in this case "task b" starts when "task a" is marked as DONE.

Is it possible for this to occur please?

Thanks
Sharon.
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