A certain computer has two identical processors that are able to run in parallel. Each processor can run only one process at a time, and each process must be executed on a single processor. The following list indicates the amount of time it takes to execute each of three processes on a single processors:

• Process X takes 40 seconds to execute on either processor.
• Process Y takes 30 seconds to execute on either processor.
• Process Z takes 20 seconds to execute on either processor.

Which of the following best approximates the minimum possible time to execute all three processes when the two processors are run in parallel?

1. Correct Answer
   Incorrect Answer
   a

   30

2. Correct Answer
   Incorrect Answer
   b

   40

3. Correct Answer
   Incorrect Answer
   c

   50

4. Correct Answer
   Incorrect Answer
   d

   60