Nitrogren gas (N2) reacts with hydrogen gas (H2) to form ammonia gas (NH3). Models of the molecules are shown.
Which model correctly shows that the mass is conserved in the reaction?
A species of small fish lives in a shady pond with a dark bottom. Some of these small fish are light colored, and some are dark colored. A new predator is added to the pond, and one of its primary food sources is the small fish. The table shows the percent of each color of fish in this population before and after the predator was added.
Students used a computer simulation to determine the variables that affect the gravitational force between two objects. They collected the data shown in the table.
Part A
Choose the claim that best agrees with the data
Globally, the quanity of almonds eaten per season has increased in recent years. Scientists claim that this increased demand for almonds will directly cause a decreased in California's limited freshwater supply. Based on the data, select the words or phrases that best complete the statement.
A tsunami is a series of waves, and it is usually caused by an earthquake. A tsunami can only be predicted after an earthquake has already occurred. Most tsunamis are caused by earthquakes over 7.0 that occur under the ocean near coastlines. These earthquakes are also less than 100 kilometers (km) below earths surface. This table summarizes the magnitude, location, and dpth of our earthquakes.
Based on this information, which earthquake has the greatest likelihood of causing a tsunami to develope?
A student wants to show a friend that a magnetic field exists in the region around a permanent magent.
For each demonstration listed in the table, select a check box to indicate whetehr the student can use the demonstration to show that a field exists in a region around a magnet.
A biologist wanted to study how cetain plant structures, such as colored flowers, might affect how oftern the plants are pollinated during the day. For one hour on a sunny summer day, the biologist oberved bee, butterfly, hummingbird, and beetle pollinators of a population of plants with equal number of purple, white, and pink flowers. Based on the data collected and shown in the table, the biologist made the claim that plants with purple flowers in the population attract more pollinators than do plants with flowers of other colors.
Which evidence could be used to challenge the biologist's claim that purple flowers in the population of plants attract more pollinators than other flower colors do?
A scientist measures the amplitude and wavelength of waves in the ocean. The scientist also calculates the amount of energy contained in one square meter of water for each wave. The data and calculations for four different waves are shown in the table.
Which wave characteristic, if any, does the energy in the wave depend on?
The diagram shows a cross section of layers of sedimentary rocks. The types of fossils in each layer are shown.
Based on the information in the cross section, select the three statements that are most likely correct.
The embryos of two vertebrate animals at the same stage of development are shown int he fiture.
Which best explains why the embryos are similar in appearance, yet the adults look different?
Plastic A is a commonly used to make disposable water bottles. Plastic B can also be used to make these bottles. Information about Plastic A and Plastic B is given in the table.
Based on the information in the table, explain two ways how using Plastic B instead of Plastic A to make disposable water bottles can help conserve natural resources. Enter your answer in the space provided.
A biologist studying a lake is concerned that an invasive aquatic plant species is outcompeting several native aquatic plant species. The native plants are the primarly food source for many animals in the lake. The biologist proposes addressing the problem by introducing a nonnative, herbivorous species of fish into the lake to eat invasive plants.
Students are asked to develope models of the solar system. One student suggests that a ball circling a pole may be used to model the Sun, Earth, and force of gravity. The model is shown in the diagram.
Which statement best describes how the model represents the Sun and Earth
Students are observing plants found in a field. The plants can be classified as native or invasive. Native plant species have been foiund in the study area for hundreds or thousands of years. Invasive plants are recent arrivals to the study area, living outside of their natural area. These invasive species, introduced by human activity, can outcompete native speices for natural resources and can replace native speices in the area.
The students monitored the field for three years, collecting data every six months. They noticed patterns of change in two thisle species, Canada thistle and Anderson's thistle.
Analyse the timeline to observe the changes to the thistles in the field over the three years.
Year 1:
Year 2:
Year 3:
Looking at the three years of observations, the students assume the environmental conditions of the field will stay the same for the next three years. Which two student predictions are most likely to include a correct description of the field after three more years.
Insects eating a plant affect how the plant grows. The students learn about three thistle-eating insects: a fly, a flowerhead weevil, and a stem mining weevil. The students want to know if these insects could affect the population of the two thistle species. The table shows the results from the students' reseach.
How would removing the Canada thistle population from the study field affect the three insect population
What would happen first to both thistle populations if the flowerhead and stem mining weeviils were both introduced to the study field during year two?
Use data from students' reaserach to explain and support your answer.
Which action would most likely increase the size of the Anderson's thisle population?