The crystal vault.
    
(some lost in space back story here, will get chatbot to generate)
(data is newly generated at each refresh.)

Your spaceship lands on the planet SNELL, and you come across an ancient alien vault that contains 
some knowledge artefacts that you seek. You realize to open the vault you needs use the vault laser 
and shoot a red laser beam to the blue receiver through a stack of crystals that are layered on top 
of each other.

Each layer of crystal has a thickness of exactly 1 unit, and there is no gap between layers.
The targeting laser beam has an initial incidence angle fixed at 45 degrees. 
This is the angle the red laser beam makes with the surface of the first layer of crystals.
Each layer of crystal is made of a different material, so the laser beam has different speeds in them. 
Let us denote v_0 to be speed of the laser before entering the crystals, and let v_i be the speed of the
laser in the i-th crystal layer.
A table of the ratios v_i/v_0 for each layer is given below, in the order that goes v_1/v_0, v_2/v_0, etc.

Find how many horizontal units has the laser beam been deflected from the vertical incidence line (shown dashed)
as it reaches the bottom of the last crystal layer.
Enter your answer in units here, round to four decimal places.
 (part 1)

(end transmission)