Use the following info to solve the questions 70 Applications and Investigations in Earth Science.1216 km²2270 km2900 km5-70 km-A Figure 4.8 Earth's internal structure.Crust(strong, rocky layer5-70 km thick)Upper mantle(rocky, includes weak.and strong layers)Lower mantle(hot, but strongbecause of highpressure)Lithosphere(strong,rocky layers)-100 kmOuter core(liquid iron)Inner core(solid iron)km/seckm/secUpper-mantle600 kmOceaniccrustLithospheric mantle(strong layer)Asthenosphere(hot, weak layer)Continentalcrust• Crust The crust is Earth's relatively thin, rocky outer skin There are two types ofcrust: continental crust, which has an average composition of a granitic rock calledgranodiorite, and oceanic crust, composed of mafic (basaltic) rocks.• Mantle More than 82 percent of Earth's volume is contained in the mantle, a rocky shellmade of ultramafic rocks that extends to a depth of about 2900 kilometers (1800 miles).The mantle's physical properties vary with depth and consist of a rigid upper layer,which, combined with the continental and oceanic crust, forms the lithosphere. Beneaththe lithosphere is the asthenosphere, consisting of weaker rocks. Beneath this weak layerthe mantle becomes increasingly stronger (more rigid) with depthLithosphere The lithosphere consists of the entire crust and uppermost mantle andforms Earth's relatively cool, rigid outer shell that averages about 100 kilometers(62 miles) in thickness.• Asthenosphere The arrow on the callout figure above implies depths closer to500+ km. Beneath the stiff lithosphere to a depth of about 350 kilometers(200 miles) lies a soft, weak layer known as the asthenosphere.• Outer core The outer core is a liquid layer 2270 kilometers (1410 miles) thick that iscomposed mainly of an iron-nickel alloy.• Inner core The inner core is a solid sphere with a radius of 1216 kilometers(754 miles), and like the outer core, it is composed mainly of an iron-nickel alloy.ACTIVITY 4.4Discovering Earth's InteriorThe study of seismic waves has improved our understanding of Earth's interior. In general, the velocities of P andS waves indicate the rigidity or stiffness of the material. Faster P and S waves indicate greater rigidity (strength).Further, S waves cannot travel through liquids because they lack rigidity. Figure 4.9 shows the average velocitiesof P and S waves at various depths. Use this figure to complete the following.1. Does the velocity of P waves and S waves increase or decrease with increased depth in the lithosphere?The velocity of P waves and S waveswith increased depth in the lithosphere.2. What are the approximate velocities of P and S waves at the bottom of the lithosphere?P wave velocity:S wave velocity:1-4.5 ©2019 Pearson Education, Inc.Asthenosphere-LithosphereCrustLowermantleOutercore2InnercoreS wavesS waves4Exercise Four / Earthquakes and Earth's Interior 7186Velocity (km/sec)10P waves1201000The asthenosphere is essrigid than the lithosphere.5. How does the velocity of seismic waves change with increasing depth in the lower mantle?200014E3000-4000-50006000▲ Figure 4.9 Illustration showing how P and S wave velocities vary with depth. Although S waves cannotpenetrate the outer core, they can still appear in the inner core. When P waves strike the boundary betweenthe inner core and the outer core, some of that energy is converted into S waves, which then travel thoughthe solid inner core.3. Does the velocity of P waves and S waves increase or decrease immediately below the lithosphere?The velocity of P waves and S waves decoimmediately below the lithosphere.4. Does the change in velocity of seismic waves as they enter the asthenosphere indicate that the asthenosphereis more or less rigid than the lithosphere?6. Does the change in velocity of seismic waves with increasing depth in the lower mantle indicate that the rockin the mantle becomes more or less rigid with depth?The rock in the mantle becomes more rigid with depth.7. What happens to S waves when they reach the outer core, and what does this indicate about this layer?8. Do P waves increase or decrease in velocity as they enter the outer core?The velocity of P waves9. What are the approximate velocities of P and S waves at the bottom of the mantle?P wave velocity:km/seckm/secS wave velocity:10. What are the approximate velocities of P and S waves at the bottom of the inner core?P wave velocity:km/seckm/secS wave velocity:11. Based on your answers to Questions 9 and 10, compare the rigidity of the material in Earth's inner core to thatof the lowermost mantle.

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Q1 . Increases Q2.  P wave velocity 70 km/sec       S wave velocity 100 km/secQ3.  likely…