Question 146419
1. The domain of the function is the range of x such that the functions makes sense. 
There are no limitations on x such that g(x) makes sense so the domain is
({{{-infinity}}},{{{infinity}}})
2. Perpendicular lines have slopes that are negative reciprocals of each other. Your given line slope is -3. The line perpendicular to the given line would then have a slope of (-1/-3) or 1/3. 
Use the point slope form of the line using the point (5,0).
{{{y-0=(1/3)(x-5)}}}
{{{y=x/3-5/3}}}
3. 
{{{h(x)=2x^2}}}
{{{h(-1)=2(-1)^2}}}
{{{h(-1)=2(1)}}}
{{{h(-1)=2}}}
{{{h(0)=2(0)^2}}}
{{{h(0)=2(0)}}}
{{{h(0)=0}}}
{{{h(4)=2(4)^2}}}
{{{h(4)=2(16)}}}
{{{h(4)=32}}}