Evolution is a

a. theory because it is an explanation that is supported by extensive observations, experimentation, and reasoning.

b. prediction because it makes an educated guess about events that will occur in the future.

c. variable because it is a factor that can be changed during experimentation.

d. law because it has been proven without exception under certain stated conditions.

the answer is a, since no one responded i chose this answer! i do not need any

Which would happen if more forests were cut down? a. the nitrogen cycle would be stopped b. nitrogen would be fixed by bacteria more quickly c. the amount of co2 in the atmosphere would increase d. fossil fuels would build up in the soil c the amount of co2 in the atmosphere would increase

Sara goes on a slingshot ride in an amusement park. she is strapped into a spherical ball that has a radius 3*10^2 of centimeters. what is the volume of air in the spherical ball? use this formula: volume of a sphere=4/3pi,r^3 , where r is the sphere’s radius.

Bisphenol a (often called bpa) is a chemical found in products that people use every day, from water bottles to food containers to children's toys. unfortunately, bpa leaches out of its many products and makes its way into our bodies. what are the health effects of bpa exposure? ongoing research is finding that elevated exposure to bpa can affect a wide variety of developmental and physiological processes, but one of the first studies of bpa's health effects came about because of a simple mistake in the lab. at a laboratory at case western reserve university in 1998, geneticist patricia hunt was making a routine check of her female lab mice. as she extracted and examined developing eggs from the ovaries, she began to wonder what had gone wrong. she noticed that many of the eggs showed problems with their chromosomes, and some had irregular amounts of genetic material, which can lead to miscarriages and birth defects in mammals. she learned that a lab assistant had mistakenly washed the plastic mouse cages and water bottles with a harsh soap, releasing bpa from the plastic. knowing that bpa is an endocrine disruptor, a chemical that can enter organisms and mimic hormones, hunt set out to discover whether it had adversely affected her mice.