$\text{If the domain of the parent graph, } y=\sqrt{x}, \text{ is } x \geq 0,\text{ what is the domain of }f(x)?$

$\text{If the domain of the parent graph, } y=\frac{1}{x}, \text{ is } x \neq 0,\text{ what is the domain of }f(x)?$

$\text{If the domain of the parent graph, } y=\text{ log}{x}, \text{ is } x > 0,\text{ what is the domain of }f(x)?$