The leading explanation for the existence of spiral arms are: Group of answer choices shock waves from cyclic supernovae explosions. shock wave from the quasar-like eruption of the galactic core. tidal streams of small galaxies being torn up by our monster Galaxy. passages of massive globular clusters through the galactic plane. passages of spiral density waves through the interstellar medium.

Urgent pls a. coal consumption levels off and remains flat. b. petroleum, natural gas, and renewables show an increase in consumption c. more nonrenewable resources continued to be consumed than renewable. d. there is little projected increase in nuclear energy use. e. carbon dioxide emissions are projected to decline as we approach 2040. global energy consumption is defined as the total energy used by an individual or organizations from around the world. use the graph above to analyze the projected energy consumption from now until 2040. which statements in the prompt apply? a) a, b, d b) b, c, d c) a, c, d d) a, b, c, d