what are d uses of map, filter, res etc

Answer 1

maps, filters and reduce are used for lists. reduce is generally used to reduce a list to a single element, for example, finding sum of all elements in a list.
maps can be used to make a new list using functions or lambda's that define the rule for the list.
filters are used to filter out specific items in a pre existing list.

Answer 2

thank you for your help

Answer 3

plz give me instances

Answer 4

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