Individuals that are heterozygous for the sickle-cell anemia allele are more resistant to malaria than those that do not have a sickle-cell allele. why does the sickle-cell allele not become fixed in the population?

Samuel is a 63-year-old single man who works full time in a food processing plant. he has a history of esophageal cancer, which was treated successfully with anti-cancer drugs and surgery four years ago. his weight had been stable at 135 pounds until 6 months ago. since then, he has experienced an involuntary weight loss of 10 pounds. he complains of a poor appetite and being overly weak, tired, and irritable. he also complains of cracks at the corners of his mouth and a chronic sore throat, which concerns him, given his cancer history. his usual diet is fairly consistent. he states that he rarely eats breakfast because he starts work at 6 a.m. he eats two deli meat sandwiches, "usually pastrami or salami," and a soda at 10 a.m., and may eat a candy bar in the afternoon when he gets off work. he often prepares and eats a frozen dinner or pizza at home in the evening and routinely drinks "about four or five beers" before going to bed. occasionally, he cooks roast and mashed potatoes for dinner and may have cereal with milk for a snack before bed. he rarely eats vegetables or fruit. 1. considering samuel's alcohol consumption, which b vitamin may he be deficient in? a. pantothenic acid b. niacin c. riboflavin d. biotin e. thiamin

Where are teens exposed to ads about tobacco products? on the radio in magazines near schools on television

Which activity causes the greatest risk of driving fatalitiesa. driving at nightb.driving while distractedc.driving with a passengerd.driving on a clear day