What are two considerations for deciding to use a roll-up summary field?
Choose 2 answers

Roll-up summary field can be performed on formula fields, but if their formula contains an #error result, it may affect the summary value.
Roll-up cannot be performed on formula field
Roll-up summary field do not cause validation rules on the parent object unless that object is edited separately.
Roll-up cannot be performed on formula fields that use cross-object references or on-the-fly calculations such as NOW()

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