Why is the troposphere important to earth?

Prior to the mt. st. helens eruption on may 18, 1980, satellite and topographic views of the volcano were captured. based on the topographic map of mt. st. helens, what is the contour interval if the volcano height is 2,950 m? question 9 options: 600 m 400 m 750 m 500 m

Amale bird-of-paradise uses a dance to attract mates in which it flaps its tail feathers on the ground and jumps around a potential female mate. a different male bird-of-paradise does a similar dance but it jumps around the female in the opposite direction. the female bird is only attracted to one style of dance, in one direction.

Which of the following statements is most likely correct about a rock belonging to the jurassic age and a rock belonging to the cambrian age? options: 1) they have identical fossils of organisms that have evolved over time. 2) both have animal fossils preserved in them due to weathering and erosion. 3) they contain different fossils because life on earth has changed through time. 4) the fossils in them were formed on the surface of earth due to exposure to sunlight.