The answers are (in order):
2nd: (some) people**
*Though not always, someone often applies to a specific unknown person;
“Someone came in today and asked about electric cars.”
EXCEPTION: in Simple Present Tense Hypothetical Narratives
“(Imagine) someone comes in and asks about electric cars; what should I tell him or her?”
**Some people refers to hypothetical people.
To come in off the street means to come or visit with no reservation, plans or schedule.