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We studied hardware support that is provided by modern processor architectures to protect TCB data and code from untrusted user code. In particular, we examined in detail the hardware support provided by successive generations of Intel processors. Answer the following questions for these processors. Provide a brief explanation that justifies your answer. In the protected mode, what descriptor protection level (DPL) is used for a segment that has TCB or kernel code and data? Also, what page protection level (PPL) is used for pages that store such segment code/data? (2+2  pts.) Does kernel code always execute at the highest privilege level?  Explain your answer. (1+2  pts.) The MOV instruction in the Intel instruction set architecture can be used to move data between registers and memory. It can also be used to load certain control registers like CR3 which stores page table base address. Consider two cases where the MOV instruction is used to load a value stored in a memory location into (i) the stack pointer register (ESP), and (ii) the CR3 register. Can the MOV instruction in each of these cases be executed by user-level code? Is MOV a privileged instruction every time it is used or it depends on its operands? Explain your answer.  (4+2+2 pts.) True or false: With the VT-x virtualization extensions and a Type I hypervisor, a system call made by user code always requires processor mode to change from non-root to root. Briefly explain your answer. (2+2 pts.) True or false: With the Intel SGX extensions, successful exploitation of a hypervisor vulnerability can result in the disclosure of sensitive data that should only be accessed inside an enclave by the enclave’s code. Briefly explain your answer. (2+2  pts.)

A nurse is preparing to administer terbutaline, a medication used to manage preterm labor, to a patient via subcutaneous injection. Which needle size and gauge should the nurse select for this administration?

Consider a normal distribution with a mean of 120 and a standard deviation of 6. Use the Empirical Rule to determine the proportion of data values between 108 and 114. Draw yourself a curve like the one below to help you answer this question.

Is the variable “Number of courses this semester” an example of a discrete or continuous variable?

Which of the following best describes declarative memory?

In a recent poll, 63% of respondents indicated that they were “worried” about climate change.  If one of the sample subjects in this poll were selected at random, what is the probability of that person having said they were “not worried” about climate change?

According to Erikson, if a child does not successfully accomplish the initiative vs. guilt psychosocial stage, which of the following associated virtues will he/she not develop?

Which functional neuroimaging modality measures the level of oxygenation in brain tissue to map the neuroanatomic activation that occurs with various challenges; provides many advantages compared to other functional imaging techniques; and has been used extensively in research involved in psychotic disorders, mood and anxiety disorders, substance-related disorders, neurocognitive and neurodevelopmental disorders, and more recently, the effects of psychotropic medications?

The scores on a test have been organized into the stem-and-leaf plot below.    What is the range of this data?

Decide if you have to use pretérito or imperfecto and write the right conjugation. 1. El martes pasado a las 10 de la mañana Ana y yo [1] (ir)  a la escuela. 2. Mis hermanas y yo siempre [2] (sentirse) muy cansadas (tired). 3. (Ser) [3] la 1:00pm.  4. Anoche, Julio [4] (tener) mucha tarea. 5, Ayer, Ana y yo [5] (comer)  un burrito. 6. Mis padres [6] (llegar) tarde frecuentemente. 7. Mi madre me [7] (dar) un carro en el 2009. 6. El fin de semana pasado, yo [8] (dormir) por diez horas. á / é / í / ó / ú