I need help with two questions.

68.An igneous rock like granite can change into a very different sedimentary rock like sandstone. What processes must have acted on the granite over the years to change this igneous material into sedimentary rock?
19. Much of the information taught in Earth-Space Science would not be available if it weren’t for our remote sensing abilities. List two topics discussed in our course and explain how our remote sensing strategies contribute to our knowledge of these topics.