text: const CustomError = require("../extensions/custom-error");
  
  const MODERN_ACTIVITY= 15;
  const HALF_LIFE_PERIOD= 5730;
  
  module.exports = function dateSample(sampleActivity) {
  let result = false;
  if (typeof(sampleActivity) === 'string') {
      let newAct = parseFloat(sampleActivity);
      if (newAct < MODERN_ACTIVITY && newAct > 0) {
          let k = 0.693 / HALF_LIFE_PERIOD;
          let res = Math.log(MODERN_ACTIVITY / newAct) / k;
          result = Math.ceil(res);
      }
  }
  return result;
  };
  