Answer:
Chunking.
Step-by-step explanation:
Chunking can be defined as a memory-enhancing strategy (technique) used by an individual to break a large data (informations) into smaller units (chunks), so as to easily store it in his or her short-term memory.
This ultimately implies that, chunking help people such as students to organize numerical data (informations) into smaller chunks or manageable bits, which are typically stored in their short-term memory.
In this scenario, to better remember his friend's phone number, Amir broke the ten numbers down into 3 bits thus, 4437576412 became 443-757-6412. Therefore, the memory-enhancing strategy that Amir used is called chunking.