Answer the following question given this paragraph: Earthquakes, essentially sound waves in Earth's crust, are an interesting example of how the speed of sound depends on the rigidity of the medium. Earthquakes have both longitudinal and transverse components, and these travel at different speeds. The bulk modulus of granite is greater than its shear modulus. For that reason, the speed of longitudinal or pressure waves (Pwaves) in earthquakes in granite is significantly higher than the speed of transverse or shear waves (S-waves). Both components of earthquakes travel slower in less rigid material, such as sediments. P-waves have speeds of 4 to 7 km/s, and S-waves correspondingly range in speed from 2 to 5 km/s, both being faster in more rigid material. The P-wave gets progressively farther ahead of the S-wave as they travel through Earth's crust. The time between the P- and S-waves is routinely used to determine the distance to their source, the epicenter of the earthquake. The speed of sound is affected by temperature in a given medium. For air at sea level, the speed of sound is given by. Q: Earthquakes have both longitudinal and transverse components, and these travel at what? Choices: - identical speeds - the speed of light - the speed of sound - different speeds A:
different speeds
(Question)
Answer the following question given this paragraph: The eardrum is like the head of a drum. It is a thin membrane stretched tight across the end of the ear canal. The eardrum vibrates when sound waves strike it, and it sends the vibrations on to the middle ear. Q: What hits the eardrum and causes it to vibrate? Choices: - cilia - decibels - microwaves - sound waves A:
(Answer)
sound waves
Ques: Answer the following question given this paragraph: Most plasma cells live for just a few days, but some of them live much longer. They may even survive for the lifetime of the individual. Long-living plasma cells are called memory cells. They retain a "memory" of a specific pathogen long after an infection is over. They help launch a rapid response against the pathogen if it invades the body again in the future. Q: What are long living plasma cells called? Choices: - device cells - context cells - brain Cells - memory cells A:
Ans: memory cells
(Q).
Answer the following question given this paragraph: Shock Hazards Electrical currents through people produce tremendously varied effects. An electrical current can be used to block back pain. The possibility of using electrical current to stimulate muscle action in paralyzed limbs, perhaps allowing paraplegics to walk, is under study. TV dramatizations in which electrical shocks are used to bring a heart attack victim out of ventricular fibrillation (a massively irregular, often fatal, beating of the heart) are more than common. Yet most electrical shock fatalities occur because a current put the heart into fibrillation. A pacemaker uses electrical shocks to stimulate the heart to beat properly. Some fatal shocks do not produce burns, but warts can be safely burned off with electric current (though freezing using liquid nitrogen is now more common). Of course, there are consistent explanations for these disparate effects. The major factors upon which the effects of electrical shock depend are 1. The amount of current. Q: A pacemaker uses electrical shocks to stimulate the what to beat properly? Choices: - brain - pancreas - liver - heart A:
(A).
heart
Ques:Answer the following question given this paragraph: The dense, iron core forms the center of the Earth. Scientists know that the core is metal from studying metallic meteorites and the Earth's density. Seismic waves show that the outer core is liquid, while the inner core is solid. Movement within Earth's outer liquid iron core creates Earth's magnetic field. These convection currents form in the outer core because the base of the outer core is heated by the even hotter inner core. Q: Seismic waves show that the inner core of the earth is solid while the outer core is what? Choices: - gas - lava - silicon - liquid A:

Ans:liquid
Answer the following question given this paragraph: The cardiovascular system transports many substances to and from cells throughout the body. Q: What system transports many substances to and from cells throughout the body? Choices: - nutritional - physiological - circulatory - cardiovascular A:
cardiovascular