newbieeyo questions

• What is the difference between applying a margin to a span element within a div tag and applying a margin within a div tag? [duplicate]
• boolean indexing with loc returns NaN
• How to group by date and by specific field in MongoDB
• Does time complexity change when two nested loops are re-written into a single loop?
• what does "either it fits or there are no more floats present" mean in the W3C specs regarding float?

newbieeyo answers