Q4.
[tex]f(x)=\sqrt{x}+4\\\\D:\ x\geq0[/tex]
Answer: all real numbers greater than or equal to 0.
Q.
The range is read from the y axis. Therefore the range = (-∞ , 1]
Answer: {y | y ≤ 0}
Q.
The first part of the graph has a slope = 2, therefore it's y = 2x.
The second part of the graph is horizontal line y= 4.
Therefore your answer is:
[tex]f(x)=\left\{\begin{array}{ccc}2x&if&x < 0\\4&if&x\geq0\end{array}\right[/tex]
