What does a variable defined as a primitive type $($int$,$ double, byte, etc.$)$ actually store?

Answer:

What does a variable defined as a reference$-$type $($i$.$e$.,$ a Class$)$ actually store?

Answer:

What is the smallest Java primitive type that could be used to store Chicago's population $(8,937,000)$

as a whole number? $($Select the one correct answer$)$

byte

short

int

long

None of these