Which of the following are true?

a. primary succession begins in an area that does not have soil.

b. secondary succession occurs in an area that already had life and soil.

c. primary succession begins in an area that did not have life before.

d. all of these are true.

Which of these is most likely to happen if parallax measurements of star distances are taken after a gap of six months? the results would be accurate the results would be inconsistent the results would not be valid the results would not be repeated

Plz fast biotechnology is a growing field of applied biology. many crops such as corn have been engineered to be resistant to herbicides. therefore farmers can spray these chemicals to kill weeds growing near the crop without worries of killing the crop itself how does this type of biotechnology work? a. by changing the genetic make up of the crops. b. by causing the crops to kill the weeds. c. by changing the type of crops used. d. by changing the location of the crops.

1. describe the structure and function of the specialized cells you observed in the video. 2. research the types of cells present in the kidney.