Completed stumped by trying to use a decimal value in an array for Bash

Here is some simple test code.

#!bin/bash 
cpm=(0 1 0.094)
lv=1
attack=5
defense=9
stamina=16
echo $((cpm[lv]))
mycpm=$((cpm[lv]))
#mycpm=echo "0.094" | bc -l
cq=echo "$attack*$defense*1/10*sqrt($stamina)*2^2*$mycpm" | bc -l
echo $cq

Terminal output:

bash testing.sh
1
72.00000000000000000000

Okay, great. Then if I change the third line to

=2

bash testing.sh
testing.sh: line 7: 0.094: syntax error: invalid arithmetic operator (error token is ".094")
testing.sh: line 8: 0.094: syntax error: invalid arithmetic operator (error token is ".094")
(standard_in) 2: syntax error

So how am I supposed to use decimals from an array? I cannot find any thing with duckduckgoing. The closest are links to for loop arrays where they figure out how to iterate by +0.1 each step. Otherwise its tutorials that all use integers. I have a preconstructed array and I just need to get values out of it to use in expressions. Line 10 will work if I actually take out the $mycpm and change that to 0.094. It'll evaluate that just fine. It's just the problem if being able to use an array to have this value. Is what I want to achieve possible in bash?