Kara uses a model that shows slight changes to earth’s motion through space over many thousands of years. this model her explain long-term climate change due to what variable?

a. volcanic activity
b. meteor or asteroid strikes
c. carbon dioxide levels in the atmosphere
d. input of solar energy

Option D, input of solar energy

Explanation:

It is clearly stated in the question that model of Kara shows the changes occurring in the motion of earth through ages. This means that as the direction of motion of earth changes the angle at which the solar rays strike the earth's surface also changes. Thus the net input of solar energy into the earths biome also changes. Sun is the major source of energy for planet earth and hence any change in solar energy input in earth will cause long term climatic changes. Also all climatic and essential geothermal, biological and nutrient cycle are governed by solar energy.

Hence, option D is correct.

The bubbles that are being produced are oxygen, which is the waste product of photosynthesis, in which the plant is producing. One conclusion that can be drawn from the relationship is that photosynthesis needs the light to occur. The light is the energy for photosynthesis to occur. If the light intensity raises then the rate of photosynthesis and oxygen also raises in response to the increase in light. Another way light intensity could be tested is the growth rate of the plant. You need to have two plants of the same species and size. One would have normal light intensity and the other would have a very increased level of intensity and then you see which one grows faster and bigger. I think one factor that would affect the procedure is glucose. The glucose is produced in amounts, during photosynthesis, that help the other reactions in photosynthesis. Without the sugar photosynthesis would no occur or it would have many defects. My hypothesis is that with an increase in light intensity the more sugar or glucose will be produced for photosynthesis. The way I will test this is have the same setup with two plants, but with the plant with the higher intensity I would measure the amount of sugar in the leaves of the plant to test the sugar level. I would then do the same thing with the regular plant and see which plant's sugar level is higher.

Explanation: these are answers to all you questions:)