Living organisms in any biome interact through a variety of relationships. Organisms compete for food, water, and other resources. Predators hunt their prey. Some organisms coexist in mutually beneficial relationships (symbiosis), while others harm organisms for their own benefit (parasitism). Still others benefit from a relationship that neither helps nor harms the other organism (commensalism).
Animals found in the Arctic tundra include herbivorous mammals (lemmings, voles, caribou, arctic hares, and squirrels), carnivorous mammals (arctic foxes, wolves, and polar bears), fish (cod, flatfish, salmon, and trout), insects (mosquitoes, flies, moths, grasshoppers, and blackflies), and birds (ravens, snow buntings, falcons, loons, sandpipers, terns, and gulls). Reptiles and amphibians are absent because of the extremely cold temperatures. While many of the mammals have adaptations that enable them to survive the long cold winters and to breed and raise young quickly during the short summers, most birds and some mammals migrate south during the winter
Answer:
The answer would be the last one, he is examining the physical characteristics. Why this is correct is because physical characteristics are visible to the naked eye and therefore everything he stated was just that, including color and shape/design
Explanation:
Answer:

Explanation:
Amount of water displaced by the sphere will be equal to the volume of complete sphere.
As the sphere completely sinks to the bottom of the cup.
We have been given;
Diameter of sphere (d) = 4.6 cm
So,

Volume of sphere (V):

By substituting value of r we get:

1 cm³ = 1 mL

V = 51 mL
So,
Water displaced by the sphere = 51 mL
Answer:
Graptolites lived from the Cambrian Period, about 510 million years ago, disappearing in the Carboniferous Period, around 320 million years ago.
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