Asap timed! 1. ice core samples from glaciers ice caps contain bubbles of ancient atmosphere that are in layers based on age. what questions are scientists most interested in? a. how the amount of water vapor needed to make the ice has changed b. how the amount of ozone has changed over time. c. how the amount of ice in each layer has changed over time d. how the amount of carbon dioxide has changed over time 2. what produces milankovich cycles ? a. sunspots ams solar flare on the suns surface b. changes in the earths orbit c. gravitational changes bases on the position of the sun and the moond. cycles of vegetation that result in desert and rainforest conditions

Hi!

The answers would be 1. (D) and 2. (B)

Ice cores are in essence drilled cylinders that are acquired from glaciers or ice sheets. Ice sheets and glaciers are formed over many years as a result of deposits of snow layers. As these layers form, the lower layers become denser with each new layer, owing to pressure, and in the process it traps the air, which is preserved in the form of bubbles in the layer, therein preserving the composition of the air at a particular period of time. Scientists use ice cores to compare the atmospheric composition of previous years to those of recent years, and the gas mainly studied is carbon dioxide owing to its bringing about a climatic change.

The Earth's orbit is caused by the gravitational attraction that is present between the Earth and the Sun, but changes due to the shape of the orbit (eccentricity), the wobble of the Earth about its axis (precession), and the axial tilt of the Earth (obliquity). These cause a change in the Earths orbit, which give rise to Milankovitch's cycles. Milankovitch's Cycles describes a revolutionary movement of the Earth around the Sun. These cycles are observed to be determinants of the climate of the Earth, in the regard of how much heat or energy the Earth is exposed to.

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it provides an alternative energy pathway for the reaction to proceed.

a catalyst is a substance that speeds up the rate of a chemical reaction but is not consumed during the course of the reaction.

catalysts increase the rate of reaction without being used up. they do this by lowering the activation energy needed. with a catalyst, more collisions result in a reaction, so the rate of reaction increases. different reactions need different catalysts.

a catalyst works by providing an alternative reaction pathway to the reaction product. the rate of the reaction is increased as this alternative route has a lower activation energy than the reaction route not mediated by the catalyst.