Plate Tectonics, that would be the answer <span />
The value of A is 78 degrees.
Answer:
1. Applying <u>the principle of original horizontality</u> -indicates that layers were repositioned from a flat-lying orientation.
2. Magma intrudes into layers of sedimentary rock and displaces them. We can deduce that the intruded magma that crystallizes is younger than the surrounding sedimentary layers by applying <u>the principle of crosscutting relationships</u>.
3. While visiting the Grand Canyon, you are amazed by the depth of layers of sedimentary rock before you, <u>the law of superposition</u>-- is evident here where progressively younger layers have formed over time and are stacked upon each other.
4. A fault cuts through layers of limestone, sandstone, and conglomerate. The surrounding layers must be <u>older</u> than the fault.
5. A mass of granite has inclusions of surrounding sandstone. The sandstone and surrounding layers show evidence of uplift over time. The granite must be <u>younger</u> than the sand deposits.
When silicon atoms bond, then silicates form which are minerals in which such elements as potassium, calcium, magnesium and aluminum combine with the silicon atoms to form minerals like feldspars of different types or if it is just silicon and oxygen that bond then it forms quartz.
