k i am not just gunna tell you what the answer are but i think i can help you find them.
1) A vertical strech, vertical being the y valus strech meaning increase, a reflection is flipping the graph about an axis, and a horizontial shift is shifting the graph left or right.
2) if f(x) is bigger then 0 and g(x) is just f(x) stretched about the vertical axis is G(x) always bigger then F(x)?
3) i really dont think so... but i have the slightest idea how to graph a linear function
maybe someone else can exsplain for the both of us?