Given the following set

$A=\{\{1,2\},1,2,\{1,2,3\}\}$

Indicate whether each of the following questions is true or false $($provide brief explanation$)$

a$.\{1,2\}inA$

b$.\{1,2,3\}inA$

c$.\{2\}subeA$

d$.|A|$

e$.\{1,2\}subeA$