These belong to the class of creature that were the first true tetrapods:
Options:
- (A) millipede
- (B) crabs
- (C) four limbs
- (D) bullfrogs
- (E) gastropod
- (F) a fish
- (G) warm-blooded
- (H) insects
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Let's think first: Amphibians are the first true tetrapods, or vertebrates with four limbs. Bullfrogs eat other amphibians. Bullfrogs are of the class of creatures that were the first true tetrapods.... So the answer is [(D)]
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An animal which may have one or two hearts to pump blood is:
Options:
- (A) squid
- (B) goats
- (C) bats
- (D) mammals
- (E) toads
- (F) Birds
- (G) edible
- (H) a fish
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Let's think first: Mollusks have a circulatory system with one or two hearts that pump blood. Interestingly, a squid is also a mollusk. Squid have a circulatory system with one or two hearts that pump blood.... So the answer is [(A)]
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The group of bipedal dinosaurs that included dromaeosaurs eventually evolved into:
Options:
- (A) insects
- (B) animals
- (C) mammals
- (D) running
- (E) Man
- (F) alpacas
- (G) genus
- (H) birds
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Let's think first: Birds evolved from a group of bipedal dinosaurs called theropods. Dromaeosaurs are part of the theropod group of dinosaurs. Birds evolved from a group of bipedal dinosaurs that included Dromaeosaurs.... So the answer is [(H)]
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What is a positive effect of plant needs for water and minerals from soil?
Options:
- (A) erosion prevention
- (B) reducing acid rain
- (C) It helps them survive
- (D) agriculture
- (E) nutrient deficiency
- (F) water run-off
- (G) erosion
- (H) Exfoliation
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Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
Let's think first: Most plants grow roots down into the soil to absorb water and minerals. Plant roots begin to stabilize the soil against erosion. The need for plants to absorb minerals and water from the soil also leads to them preventing soil erosion.... So the answer is [(A)]
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