
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
A point M($\sqrt {3}$,-1) on the circle O: x<sup>2</sup>+y<sup>2</sup>=4 is given. A tangent line is drawn from point M to the circle O, and a line l is drawn through the point ($\sqrt {3}$,2) perpendicular to the tangent line. The line l passes through the focus F of the parabola E: x<sup>2</sup>=2py (p>0).
(1) Find the equations of line l and parabola E;
(2) Lines y=k<sub>1</sub>x+2 and y=k<sub>2</sub>x+m intersect parabola E at points A, B and C, D respectively, and AC intersects BD at point (0,1). Find the value of $\frac {k_{1}}{k_{2}}$.

Present the answer in LaTex format: \boxed{Your answer}
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