The concentration of carbon dioxide in the atmosphere in 1958 was 310 ppm and rose to 390 ppm in 2009. the percent increase in carbon dioxide over this period of time is closest to:

Which of the following is not a major characteristic used to identify minerals? a. hardness c. density b. magnetism d. luster select the best answer from the choices provided a b c d i know it is not d

Dr. kaylan is an ecologist who studies bird behavior. she sets up an experiment to test which type of food crows are most likely to eat when given a choice between walnuts, corn, and sunflower seeds. to perform her experiment, dr. kaylan places three food bins in an area frequented by cows. each bin contains one of the three food types. then, she measures how much of each food type is eaten every day for a month and summarizes the results of her experiment in the pie chart below. based on her results, dr. kaylan concludes that crows choose to eat corn more frequently than other food sources because it has a higher nutritional value. what is a reasonable alternate conclusion that can be drawn from dr. kaylan's data

The first signs of cellular differentiation occur in the blastocyst. why is cellular differentiation important for the development of a fully formed human infant?