Which of these is the best explanation of how a smooth round stone became smooth?
A. continuous freezing and thawing
B. volcanic action
C. it fell
... [Show More] off the side of a cliff
D. it was in a stream for a long time
D. it was in a stream for a long time
When a lobster grows a claw to replace one that was lost, the process is called
A. restoration
B. retraction
C. regeneration
D. reproduction
C. regeneration
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Any astronomical body that revolves around a larger body is called
A. a nova
B. a comet
C. a satellite
D. an astroid
E. a meteoroid
C. a satellite
In chemistry, to be classified as an organic substance must contain
A. sugar molecules
B. sodium atoms
C. carbon atoms
D. water molecules
C. carbon atoms
According to their locations on the Periodic Table, argon (Ar) and neon (Ne) are
A. ionic
B. radioactive
C. liquid metals
D. noble gases
D. noble gases
To test the effectiveness of plant fertilizer, groups of plants are grown with different types of fertilizer. A control group of plants would
A. not be given any fertilizer
B. be grown with a mixture of all fertilizers
C. not be needed unless the results were unclear
D. be grown in a different location from the other groups
A. not be given any fertilizer
When scientists measure a liquid's resistance to flow, they are measuring he liquid's
A. density
B. solubility
C. viscosity
D. permeability
C. viscosity
Regeneration in man is limited to
A. reproduction
B. fertilization
C. experimentation
D. healing of wounds
D. healing of wounds
By definition, an aquifer is
A. a layer of sedimentary rock formed by water deposits
B. an ocean floor consisting of unconsolidated sediments and muds
C. river bottom made up of gravel and sedimentary rock
D. permeable rock that contains or carries water
C. river bottom made up of gravel and sedimentary rock
Which of the following reproduce by spawning?
A. butterflies
B. birds
C. bats
D. fish
D. fish
Which of the following is the best illustration of centripetal force?
A. ice skater spinning on the ice
B. skier zigzagging down a slope
C. bicycle rider coasting down a hill
D. scuba diver descending in the water
A. ice skater spinning on the ice
In a balanced aquatic ecosystem, which of the following would have the greatest population?
A. fish
B. crabs
C. sharks
D. plankton
D. plankton
Using the list, which of the following presents the stages of the water cycle in the correct order?
1. water vapor cools
2. precipitation occurs
3. evaporation occurs
4. condensation occurs
5. sunlight heats pond water
A. 1 => 4 => 2 => 5 => 3
B. 5 => 2 => 1 => 4 => 3
C. 1 => 3 => 2 => 4 => 5
D. 5 => 3 => 1 => 4 => 2
D. 5 => 3 => 1 => 4 => 2
if you place bean seeds between moist paper towels and watch the stem and leaves appear you will see a demonstration of ?
germination
which element does not contain any neutrons?
Hydrogen/protium
what is the symbol for hydrox ion
OH-
a perpetual motion machine can never be built because it's not possible to eliminate??
elasticity [Show Less]