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Which of the following viruses does not have an approved vaccine?

Which of the following is not considered a high-risk population for the flu? 

Parasites are smaller than prions 

This exam is timed. You may use your notes, textbook or study guide. The use of AI is prohibited and will result in a zero if discovered. 

In the following five questions, you will be asked to match each taxon (mosses, monocots, conifers, ferns, and cycads) with their characteristics. The list of possible answers is the same for each group. Answers may be used for multiple taxa. If some but not all members of the group have the characteristic, include it.   

Mortality due to disease is generally low in natural plant communities, but can often be high in crops. Explain why this is the case (I expect at least 3 contributing causes).  

This is a BONUS question. Answering it will provide you with up to 4 extra points. You have been kidnapped by the League of Brilliant but Overenthusiastic Bumbling Botanists (the BOBBS). They are threatening to tickle your teddy bear until it squeals UNLESS you manage to convince one fellow student who is currently indifferent or hostile to plants that they should take a plant course. What arguments would you use to get yourself and your teddy bear out of this precarious situation?  

For each of the following pictures, indicate what taxonomic group (scientific or common name) the plant belongs to.  Be as precise as possible (i.e. use the lowest taxonomic group you know). A:                                B: C:                        D:

Enterprises are increasingly relying on Cloud services (e.g., Amazon AWS) for a variety of reasons. In this question, we want to explore storage and processing of data in a Cloud environment when there are mandatory access control requirements for the data. Assume authentication and authorization are correctly implemented in a public cloud where resources are shared among multiple applications that belong to different tenants who compete with each other (e.g., two banks). Answer the following questions for this system. A hypervisor allocates resources to various virtual machines (VMs) in the Cloud environment. If the Cloud uses elastic resource allocation, which moves resources across VMs dynamically, covert channels could be a concern. Answer the following questions for this system. If CPUs can be reallocated between different tenants dynamically, can this lead to a covert channel? If your answer is yes, give an example of a covert channel and explain how it can be set up. (2+2 pts.) If you give an example of a covert channel in 1.I, is this a timing or storage covert channel? Explain your answer. (2 pts.) If your answer for question 1.I is yes, would the channel be noisy? Explain your answer. (2 pts.) True or false: Side channels are not a concern in the above Cloud environment. Explain your answer. (2 pts.) Can a storage covert channel be created in this system which allows data to be transferred from tenant T1’s process to a process of tenant T2. Explain your answer by showing how a covert channel can be set up or why it is not possible. (1+2 pts.) Assume it has been determined that the Cloud provider must address covert channel concerns of its tenants. We discussed several techniques for mitigation of covert channels. Two examples of such techniques are static resource allocation and the pump. Can timing covert channels be mitigated with static resource allocation? Explain your answer. (1+2 pts.) Could the pump be used for covert channel mitigation in an environment where applications of different tenants do not interact with each other? Explain what types of covert channels can be mitigated using a pump. (2+2 pts.) Could the shared resource matrix (SRM) be used to detect covert channels in such a system when different tenant applications run in separate virtual machines? If yes, explain how or discuss why it is not possible. (2+2 pts.) Assume that when user U’s process P makes a request for file F in SELinux, discretionary and type enforcement (TE) permissions are granted.  In the multi-level security (MLS) part of the security context of F, the security level is s5. You can assume that both F and U have their compartment set to co..c1023. Answer if the following statements are true or false, and briefly explain your answer. U can never read F when the effective security level in its security context is s4. (2 pts.) U can always read F when the clearance level in its security context is s6. (2 pts.) U may be able to read F when its effective security level is s3 and its clearance level is s6. Explain your answer. (2 pts.)

Which hormone is mainly produced by the ovaries?