Carbon absorbs energy at a wavelength of 150. nm. The total amount of energy emitted by a carbon sample is 1.98 x 105 J. Calculate the number of carbon atoms present in the sample assuming that each atom emits one photon.

Jewelweed, a flowering plant, has seed pods that burst open when touched and forcefully eject their seeds. these structures are favorable because they a. can cause genetic changes to occur. b. prevent germination within the seed pod. c. aid in the dispersal of the species. d. attract insects that aid in pollination.

Harvey kept a balloon with a volume of 348 milliliters at 25.0˚c inside a freezer for a night.  when he took it out, its new volume was 322 milliliters, but its pressure was the same.  if the final temperature of the balloon is the same as the freezer’s, what is the temperature of the freezer? the temperature of the freezer is  kelvins.

Design techniques and materials that reduce the negative environmental impact of a structure are referred to as