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The map below shows the location of the Chicxulub impact crater, which was formed in the Gulf of Mexico approximately 65.5 million years ago. With an estimated 108-mile diameter, this crater, which is now buried beneath surface crustal rocks, is one of the largest craters on Earth.
The asteroid impact that formed this large crater is theorized to have caused*
Base your answers to questions 2 on the graph below and on your knowledge of Earth science. The graph shows the number of families (groups of closely related species) represented in the fossil record and fi ve major mass extinction events in Earth’s history.
One group of organisms that existed on Earth before 550 million years ago was*
Which event occurred approximately 4.6 billion years ago?*
Approximately how many million years ago (mya) were all of Africa and South America inferred to be located south of the equator?*
Base your answers to questions 5 on the passage below and on your knowledge of Earth science.
Earth has undergone many ice ages, each lasting millions of years. Some scientists infer that most ice ages were caused by landmasses blocking the ocean currents between equatorial regions and the poles. Ice ages usually ended when the positions of continents allowed ocean currents to resume transporting equatorial heat to the poles.
During each ice age there were advances and retreats of glaciers. These cool glacial and warm interglacial climate intervals were caused mostly by changes in Earth’s orbit and tilt. Earth is presently in a warm interglacial interval.
Approximately 359 million years ago, the average intensity of insolation received in a year by the land area that is now eastern North America was likely*
Base your answers to questions 6 on the cross section below and on your knowledge of Earth science. The cross section represents the landscape features and rock units of the Grand Canyon region in the southwestern United States. The names and ages of some rock formations are shown.
Approximately how many million years ago (mya) was the Coconino sandstone deposited as sediment?*
The map below shows the location of the Chicxulub crater, which was formed when a massive asteroid impacted Earth 65.5 million years ago.
Scientists infer that this impact contributed to the extinction of*
Labeled lines on the map below show the inferred location of Earth’s equator during the middle of several geologic periods.
Approximately how many million years ago (mya) was the region around current-day Watertown, New York, located the nearest to the equator?*
Base your answers to questions 9 on the information and diagram below and on your knowledge of Earth science. The diagram represents a simplified model of the early formation of Earth’s interior.
Early in its formation, Earth was a molten mass of evenly mixed composition. During the next few million years, the heavier and more dense elements sank to the center, while lighter and less dense elements rose toward the surface. This is called chemical fractionation.
Approximately how many years ago did Earth and other planets in our solar system begin the process of chemical fractionation?*
The formation of the planet Uranus is estimated to have occurred approximately*
Base your answers to questions 11 on the passage and geologic cross section below and on your knowledge of Earth science. The geologic cross section represents rock layers of a portion of the Niagara Escarpment, and landscape features that are found in the Niagara region. The rock layers have not been overturned.
The Niagara Escarpment
A prominent feature found along the shore of Lake Ontario in western New York State is the Niagara Escarpment. This escarpment is the remains of an ancient seabed that was formed when the area was covered by a warm, shallow sea from approximately450 to 430 million years ago. Erosion of the Taconic Mountains to the east provided
the sediments deposited in this basin area. From these sediments, rock layers such as shale, sandstone, and limestone formed. Later, magnesium replaced some of the calcium in the top layer of limestone, turning it into a dolostone layer. When the high ocean levels of the Ordovician Period dropped, the draining of this inland sea caused unequal erosion of the exposed layers. The South Moraine was deposited on the top of the Niagara Escarpment in this region.
Describe the tectonic event that caused the Taconian orogeny. *
Base your answers to questions 12 on the side-view model of the solar system in image provided and on your knowledge of Earth science. The planets are shown in their relative order of distance from the Sun. Letter A indicates one of the planets.
How many million years ago did Earth and the solar system form? 
million years ago*
Base your answers to questions 13 on the generalized cross section of the Grand Canyon represented below and on your knowledge of Earth science. Some rock layers have been labeled. The rock layers have not been overturned.
State the approximate age of the Redwall limestone, in million years. 
Base your answers to questions 14 on the diagram below and on your knowledge of Earth science. The diagram represents five inferred stages in the formation of our solar system. Stage 1 represents a contracting gas cloud. Stages 2 through 4 represent the gas cloud flattening into a spinning disk as planets formed around our Sun. Stage 5 represents the final stage in the formation of the solar system.
State the number of million years ago (mya) for the estimated time of origin of our solar system. *
Base your answers to questions 15 on the passage below.
Meteors that strike Earth’s surface are called meteorites. Analysis of meteorite composition has provided scientists with information regarding the formation of Earth and our solar system, and possibly the development and evolution of life on Earth.
Two types of meteorites are iron meteorites and chondrites. Iron meteorites consist mostly of iron and nickel, and are inferred to be from core materials of early planetary bodies in our solar system. More than 60% of meteorites studied have been identified as chondrites. Chondrites are made of millimeter-sized spheres of olivine and pyroxene crystals embedded in a mass of mineral and metal grains. The chondrites are thought to represent fragments of the earliest solid materials in our solar system. One type of chondrite, the carbonaceous chondrite, contains water, organic compounds, and minerals that represent the chemical composition necessary for life to form.
What is the estimated age, in years, of Earth and our solar system?