Define a relation S from ℤ to ℤ, where x y means x squared equals y where x ∈ ℤ and y ∈ ℤ. a) Write S as a series of ordered pairs in set-roster notation (remember, you can use …ellipses…)b) Write S in set-builder notation. c) Does the relation S meet the criteria to be a function

Write a computer program to calculate the three-phase fault current for a fault at f in figure 1.16, with the network normal, and with one line at a time removedproblems 1.1 write a computer program to calculate the three-phase fault current for a fault at f in figure 1.16, with the network normal, and with one line at a time removed 20 power system relaying from service. the positive-sequence impedance data are given in the accompanying table. use the commonly made assumption that all prefault resistance values are (1.0+j0.0) pu, and neglect all resistance values. calculate the contribution to the fault flowing through the cb b and the voltage at that bus. for each calculated case, consider the two possibilities: cb b2 closed or open. the latter is known as the stub-end fault í• figure 1.16 problem 1.1 system data for figure 1.16 from to positive sequence 0.0+j0.1 0.05j0.15 0.04 j0.2 0.01 jo.i 0.015 + j0.15 0.01 j0.19 0.01 +j0.19 0.03+j0.1 0.0+j0.08 6 6 6 from service. the positive-sequence impedance data are given in the accompanying table. use the commonly made assumption that all prefault resistance values are (1.0 + j 0.0) pu, and neglect all resistance values. calculate the contribution to the fault flowing through the cb b1, and the voltage at that bus. for each calculated case, consider the two possibilities: cb b2 closed or open. the latter is known as the “stub-end” fault.

Create a word problem that involves calculating the volume and surface area of a three-dimensional object. cube: surface area 6 s2 , volume s3

Write the command that can be used to answer the following questions. (hint: try each out on the system to check your results.) a. find all files on the system that have the word test" as part of their filename. b. search the path variable for the pathname to the awk command. c. find all files in the /usr directory and subdirectories that are larger than 50 kilobytes in size. d. find all files in the /usr directory and subdirectories that are less than 70 kilobytes in size. e. find all files in the / directory and subdirectories that are symbolic links. f. find all files in the /var directory and subdirectories that were accessed less than 60 minutes ago. g. find all files in the /var directory and subdirectories that were accessed less than six days ago. h. find all files in the /home directory and subdirectories that are empty. i. find all files in the /etc directory and subdirectories that are owned by the group bin."