how to use ploted to draw a line of "x=0"



Dear all

I use plot2d to draw "log(x),exp(x) relation  on x,y , x=y axis"
this is my command
f(x):=x;
plot2d([exp(x),-exp(x),log(x),-log(x),f(0),f(x)],[x,-5,5],[y,-5,5]);

that is my question
1. how to draw the line of "x=0" (i.e. y-axis)
2. how to change the color and line type of "set grid" line
3. how to show the "intersection point" of  exp(x) and log(x),x-axix, y-axis
4. how to show the scale of x : y = 1:1(because the x scale is a littel long to y scale)



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