Susan must enter the number into her phone right away because she has about 15 to 20 seconds before her short term memory store is depleted.
Memory is basically storing the information in the mind. It takes up all the information, data, facts and figures and stores in the brain.
Susan has only around 15 to 20 seconds before her short-term memory reserve runs out, so she needs to immediately type the number into her phone.
Learn more about Memory here:
https://brainly.com/question/8053990
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