*Question*
If birds are endothermic vertebrates with legs, then what are endothermic vertebrates with legs? Answer choices: - Birds - mammals - Snakes - ducks - Lizards - ants - long - toads
**Answer**
Birds

*Question*
If exposure to cold can induce many muscle fibers to contract at once, then many muscle fibers contracting at once can be induced by? Answer choices: - exposed genitalia - exposure to heat - sweating - exposed biceps - mechanical waves - Electrical energy - exposure to cold - Veins and arteries.
**Answer**
exposure to cold

*Question*
If parts of the Earth's crust being pushed together causes earthquakes, then parts of the Earth's crust being pushed together causes what? Answer choices: - magnetic shifts - erosion - friction - earthquakes - solar flares - moonquakes - global warming - Sediment
**Answer**
earthquakes

*Question*
If something that can be smooth can only contract, then something that can be described as what can only contract? Answer choices: - Smooth - the skin - Rough - strong - Sweet - Loud - complex - alveoli
**Answer**
Smooth