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Assume we are using a simple model for floating-point (the representation uses a 14-bit format, 5 bits for the exponent with a bias of 15, a normalized mantissa of 8 bits, and a single sign bit for the number):   1. Show how the computer would represent the numbers 100.0 and 0.25 using this floating-point format.   2. Show how the computer would add the two floating-point numbers in part 1 by changing one of the numbers so they are both expressed using the same power of 2.

Suppose we have just found yet another representation for floating point numbers. Using this representation, a 12-bit floating point number has 1 bit for the sign of the number, 4 bits for the exponent and 7 bits for the mantissa, which is normalized as in the Simple Model so that the first digit to the right of the radix points must be a 1.  Numbers in the exponent are in signed 2’s complement representation.  No bias is used and there are no implied bits.  Show the representation for the smallest positive number this machine can represent using the following format.  What decimal number does this equate to?              

Why do we usually store floating-point numbers in normalized form?  What is the advantage of using a bias as opposed to adding a sign bit to the exponent?

If the floating-point number representation on a certain system has a sign bit, a 3-bit exponent and a 4-bit significand: What is the largest positive and the smallest positive number that can be stored on this system if the storage is normalized? (Assume no bits are implied, there is no biasing, exponents use two’s complement notation, and exponents of all zeros and all ones are allowed.)         What bias should be used in the exponent if we prefer all exponents to be non-negative?    

A task runs alone on a CPU. The task starts by running for 5 ms. The task then waits for 4 ms while the operating system runs some instructions to access disk. The CPU is then idle for 2 ms while waiting for data from disk. Finally, the task runs another 10 ms and completes. (2.5 points)   a. The elapsed time is ________________ ms.     b. The user CPU time is ________________ ms.     c. The CPU time is _____________ ms.     d. The system performance is _______________ ms.     e. The CPU performance is ______________ ms.

A victim’s estate filed a wrongful death action against a defendant, alleging that she murdered the victim. The victim was killed at 3:00pm, and the defendant has claimed that she could not have done it because she was at work when it happened. At trial, the victim’s estate called the defendant’s co-worker to the stand, expecting him to say that he noticed the defendant leave the office at 2:00pm on the day of the murder. However, on direct examination, the co- worker testified that he saw the defendant leave the office at around 4:00pm. After giving theco-worker the opportunity to explain or deny his statement made at his deposition that the defendant left the office at 2:00pm on the day of the murder, the victim’s estate seeks to introduce the deposition statement into evidence.  Is the co-worker’s statement from the deposition admissible?

Marge is setting up access controls for her company’s AWS infrastructure. She wants to ensure that Homer can only view specific S3 buckets, while Bart has full administrative rights to EC2 instances, and Lisa can only access billing information. Which AWS service would allow Marge to implement these different permission levels?

Ned needs to deliver his company’s website content, videos, and APIs to customers globally with low latency and high transfer speeds. Which AWS service should Ned use?

Selma serves as the Chief Information Officer for her organization and must ensure that security objectives for visibility, auditability, control, and agility are met during the AWS cloud migration. Which AWS Cloud Adoption Framework (CAF) perspective would be most appropriate for someone in her position?

Nelson is evaluating two different IT infrastructure options for his business. Option A requires him to purchase and install equipment on his own premises, while Option B allows him to pay a cloud provider based on actual usage. Which statement best describes the key difference between these two approaches?