Which statement is correct regarding to smith chart?

All $r-$ and $x-$circles pass through point $({}_r,{}_i)=(1,0)$

Any impedance repeats itself every $\frac{}{4}$ on the Smith chart

An $s=2$ circle is the same as $|r|=0\mathrm{.}5$ circle on the Smith char

The slotted line is used to determine $Z_L$ only