The Precambrian Era is the least understood part of Earth history, yet it is arguably the most important. It began with the formation of Earth nearly 4.6 billion years ago, and lasted for approximately 4 billion years. During this time, all of Earth’s major systems appeared, such as the hydrosphere, biosphere, geosphere, and atmosphere. The Precambrian Earth experienced impacts by massive celestial objects, the first continents and ocean basins, mobilization of tectonic plates, an oxygenated atmosphere, and the origin and evolution of early life. Not only did life begin and survive during this challenging, harsh time period, but it thrived and continued to evolve. The evidence for the story of the Precambrian era is within Earth’s rocks. Where on Earth’s surface do you think scientists can locate rocks from the Precambrian era? How do scientists determine the age of the rocks they’re analyzing? What types of tests or analyses do you think scientists would conduct on a rock from the Precambrian era? Lastly, how does understanding the Precambrian era enhance our chances of finding another planet that could one day support life?

the answer is; comparing the frequency of collisions with and without the device

this makes the anti-collision system an independent variable and the collisions a dependent variable. if there are fewer collisions with an anti-collision system that without, then it can be stated that the system is a success. essentially, collisions under an anti-collision system are compared with the frequency of collisions by cars with the human drivers.

answer: angiosperms

dicots

angiosperms are highly evolved plants, they produce seeds which are enclosed within in a carple. these are the largest group of plants on earth. they include trees, shrubs, herbs and small flowering plants. angiosperms exhibit a flowering stage in their life cycle. the flower serves the function of reproduction and fruit formation in majority of angiosperms. dicot is the term used to describe flowering plants that have two seed leaves. dicots are plants which develop seeds which split into two parts called cotyledons. each cotyledon contains one embryo.

here, a small purple flower development indicates that the plant belongs to angiosperms and having two embryonic leaves indicates it belongs to dicots.  

answer : haversian

[explanation: -(compact bone is organized as parallel columns, known as haversian systems, which run lengthwise down the axis of long bones. these columns are composed of lamellae, concentric rings of bone, surrounding a central channel, or haversian canal, that contains the nerves, blood vessels, and lymphatic system of the bone)]

the answer is sex-linked recessive.