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7. Stock Option Plans and Agreements (Details)
6 Months Ended
Jun. 30, 2019
Expected dividend yield 0.00%
Expected stock price volatility 100.00%
Minimum  
Risk-free interest rate 2.17%
Expected life of options 3 years
Maximum  
Risk-free interest rate 2.55%
Expected life of options 3 years 10 months 24 days