text: const MODERN_ACTIVITY = 15; 
  const HALF_LIFE_PERIOD = 5730;
  
  module.exports = function dateSample(sampleActivity) {
    if (sampleActivity && typeof sampleActivity === 'string') {
      const activity = parseFloat(sampleActivity);
      if (!isNaN(activity) && activity > 0 && activity < 15) {
        const k = 0.693 / HALF_LIFE_PERIOD;
        const result = Math.ceil(Math.log(MODERN_ACTIVITY / activity) / k);
        return result;
      }
    }
  
    return false;
  };
  