A medical facility does MRI for sports injuries. Occasionally a test yields inconclusive results and must be retested. Using the following sample data and n$=50.$

sample ID $12345678910$

# of retest $1220212729$

The upper control limit for a $2-$sigma control limit level chart is $\_\_\_\_\_\_.($Please keep $3$ decimals for your final answer$)$

Hint: Please keep $4$ decimals in the middle of calculation. Don't round it up too soon.