A certain genetic mutation is found with a high frequency in populations of humans living in places that experienced a deadly disease in the past. This same mutation is rare in places that have no history of the disease. Based on how genes work, this data best supports which of the following explanations?

Explanation for basic character?

Let the ed50 of a recreational drug be defined as the amount required for 50% of a test group to feel high or get a buzz. if the ed50 value of ethanol is 470 mg/kg body mass, what dose would a 70 kg party goer need to quickly consume in order to have a 50% chance of getting a buzz? 235 mg 470 mg 32,900 mg 35,000,000 mg

Salt in oceans comes from and of rocks