Let's Check Your IQ

Figure out how many trailing zeroes are in 1000! 

I have 4 corners. I have 4 sides.

I have 2 long sides and 2 short sides.

Who I am?

Can you solve it?

E + E + E = 15

E + C = 8

C + E + B = 10

B + C * J = ????

What goes up but never comes down?

What am I?