Which of the following best describes why longitudinal waves cannot travel in space?

a) longitudinal waves can travel without a medium

b) gravity interferes with the travel of longitudinal waves in space

c) there are too few air particles in space for longitudinal waves to travel

d) space contains too many particles that interfere with the travel of longitudinal waves

Ineed to get this test done which of the following statements is correct in hour our immune system responds to a potential pathogen? a.) the skin will be the first line of defense, and then the many phagocytes in the bloodstream will attempt to consume the possible pathogen. b.) b cells will start reading the antigen code immediately and call t cells to assist in destroying the pathogen. c.) the adapted immune system will call on the innate immune system to destroy the pathogen. d.) the t-cells in the adapted immune systems are the first to recognize the pathogen