Given the background description of some cooking related query, summarize the question into a title

[EX Q]: How do you prepare fresh fennel for cooking? My isntructions just say to "roughly chop", but don't say what parts of the plant to use.
[EX A]: How do you prepare fresh fennel for cooking?

[EX Q]: My local supermarket was out of 1% milk today, so I decided to get half a gallon of 2% and half a gallon of skim milk and combine the two at home. Now I'm wondering in what I should store the combined milk...I still have a 1 gallon container from the last milk I purchased which I can use. There's a tiny bit of milk left in there, but it will be finished by today. The only thing I'm worried about is that, even if I wash the container the best I can, it will still have traces of bacteria in there from the old milk. Does this mean, then, that I should treat the expiration date of the combined milk as the same date printed on the old container?Should I store the milk in some other container (e.g. a pitcher)? Should I temporarily combine the two in a pitcher, then put them back in the two half gallon containers they came with? Any other ideas?
[EX A]: Which container to use for combined milk?

[EX Q]: Many a recipe or package instructs: 'cook uncovered' without stating a reason. As a general matter, is this to protect me from boilover, or does it have some more subtle purpose?
[EX A]:
When a recipe says, 'simmer uncovered', what's the issue?