Maglev trains float on a cushion of air, eliminating friction. this lack of friction and the trains' aerodynamic designs allow these trains to reach unprecedented ground transportation speeds of more than 310 mph (500 kph). developers say that maglev trains will eventually link cities that are up to 1,000 miles (1,609 km) apart. at 310 mph, you could travel from paris to rome in just over two hours. magnetic levitation (maglev) trains use electricity to generate magnetic fields. how are these magnetic fields related to the forward motion of the train? a) electricity is used to generate a magnetic field opposite that of the train so the train is pulled forward along a frictionless surface. b) electricity is used to generate a magnetic field of the same polarity as that at the base of the train. this elevates the train and also moves it forward. c) electricity generates a magnetic field as it flows through coils on the train. a large electromagnetic at the opposite end of the track pulls the train to its destination and lifts it off the track. d) a current below the train generates a magnetic field that levitates the train, by using the repulsion of like charges. electricity flows through coils on the side of the track, as the current alternates it pulls the train forward and pushes it from the back.

Plz dont type in wrong or just say something to get all my ponit if you do thing willl happen > : l in an environment can destroy entire ecosystems. these changes can occur quickly or over time. which environmental change occurs fastest? volcanic eruption regrowth of forest after volcanic eruption pond succession decomposition of a treeover time the trees in african have increased in length. many species have had to adapt to this change in order to survive. which of the following is a structural adaptation that has the african giraffe meet this change? question 11 options: the african giraffe has become a faster at running from its predators. the african giraffe's neck has increased in size over the years. the african giraffe have moved to another part of africa. the african giraffe has not adapted and struggles to survive. eve and sammy are discussing the affects of farming on the environment. eve states that farming does not harm our environment. she believes that it is only beneficial for the ecosystem and species living in it. sammy states that farming can have major impacts on the environment. he believes farming can cause habitat loss. who is correct? question 12 options: eve is correct because farming only leads to positive affects on ecosystems. sammy is correct because farming has major affects on the environment including soil erosion and flooding. eve is correct because farming does not lead to soil erosion and flooding. neither of them are correct. a power plant recently purchased land and will be building a large factory on wetlands in florida. which of these is not an environmental effect of destroying these wetlands? question 13 options: destroying the wetlands will create a loss of habitat for many species. destroying the wetlands will create flooding. destroying the wetlands will create species to relocate to a new area. destroying the wetlands will change the climate in this area.ever since non-native mussels were introduced into the great lakes, they have caused ecological problems. mussels are very efficient filter feeders. they are better at filtering algae from the water than native species are. which of the following would not result from mussel introduction? question 14 options: excessive growth of mussel populations decline in populations of native mussel species water becoming clearer because mussels eat more algae excessive growth of algae that kills other organismswhat would be an immediate effect of the construction of roads and parking lots on the transfer of energy from producers to consumers in an ecosystem? question 15 options: a decrease in the number of producers a decrease in the number of consumers an increase in the number of producers an increase in the number of consumers

Water at room temperature of 20.0°c is poured into an aluminum cylinder which has graduation markings etched on the inside. the reading in the graduations is 300.0 cc. the cylinder with the water in it is then immersed in a constant temperature bath at a temperature of 100°c. what is the reading for the level of water on the graduations of the cylinder after the water and the cylinder reach thermal equilibrium with the bath? the volume coefficient of expansion of water is 2.07 x 10^-4 k-1, and the linear coefficient of expansion of aluminum is 23.0 x 10^-6 k-1. a) 305.0 cc b) 304.0 cc c) 303.5 cc d) 303.3 cc e) 304.5 cc

Work out sian speed for the first 30 minutes of her journey. give your answer in km/h.