Answer:
Magma is less dense than the surrounding rock which causes it to rise. When magma reaches the surface it is then called lava and the eruptions of lava and ash produce volcanoes. The lava that reaches the Earth's surface will harden and become igneous rock.
Explanation:
Answer: d) lightheadedness or unconscious episodes.
Explanation:
There are several ways the body responds to stress but one method used by psychologists to measure this response is Hans Selye's general adaptation syndrome. This occurs in 3 stages:
1. The alarm reaction. This occurs when the stressor is first presented resulting in the RELEASE OF HORMONES from the adrenal gland into the blood stream. The hormone in turn cause sympathetic nervous system activation and increase energy levels, INCREASE RESPIRATION, increase muscle tension, reduce sensitivity to pain, slow down the digestive system, and cause a RISE IN BLOOD PRESSURE.
2. The stage of resistance- this occurs till the stress is removed.
3. The stage of exhaustion
<em />It's radiocarbon dating because in the previous question it says that she is trying to find the amount of carbon-14 and carbon-12 in the fossil
Answer:
1- Option A) describes an index fossil. Trilobite existed for a short time, but was abundant and lived in many locations.
2- Option B) Continents were once joined and have since drifted apart.
Explanation:
1) Fossils are animal and vegetable rests found in different strata of sedimentary rocks. Sedimentary layers deposit chronologically, so they are used to reflect history. They keep in each layer some of the forms of life that inhabited that area in the past. These fossils turn to be very useful while dating ages. The term Index fossils refer to those fossils that only existed in a given era or geological period during evolution.
Index fossils must:
• Be easily recognizable and distinguishable from all the other fossils
• Have lived in a relatively short geological period
• Present a wide geographic distribution
• Have lived in different sedimentary basins
• Appear in different types of rocks
• Be abundant
<em>A) Trilobite existed for a short time, but was abundant and lived in many locations. </em>The species accomplish the requirements. It is easily recognizable, had a wide geographic distribution, was abundant, and lived for a short time.
2) The tectonic plates theory states that there is a continual movement of the crust. It explains the movement of the different plates and their directions and interactions. The continental drift theory explains how these movements have been taking place since millions of years ago. When continents were together in a unique continent, many species used to inhabit it. When plates started to separate, they took some of these species that got apart by the ocean. Some species were already dead and fossilized, while some other organisms died during continental drift and got fossilized after the divergence. <em>The existence of the same fossils, placed in the same layers and of the same age, suggests that they used to inhabit the same area and died during the same time, meaning that continents were together when they got fossilized. </em>
