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题库 / Prep2007E2-SC-121
Changes in the composition of the light of a supernova--an exploding star--reveals not only the chemical elements in the explosion but also the speed of expanding the outer layers of stellar gas.
reveals not only the chemical elements in the explosion but also the speed of expanding the outer layers of stellar gas
reveals not only what chemical elements are in the explosion but also the speed at which the outer layers of stellar gas are expanding
not only reveal the chemical elements in the explosion but also the speed of the expanding outer layers of stellar gas
not only reveal what chemical elements are in the explosion but also the speed of the outer layers of stellar gas when they are expanding
reveal not only the chemical elements in the explosion but also the speed at which the outer layers of stellar gas are expanding
the speed at which。。