What substance was the first photograph made from?

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.

Linux is distributed under gnu gpl. why is this important? a. it ensures that only torvalds can profit from the sale of linux b. it prevents unknowledgeable users from downloading programs they don't know how to operate. c. it provides protection for the developers who created linux. d. it states that anyone can copy, modify, and share the program if changes are made public.

Complete the sentence about a presentation delivery method