Final answer:
The question on splicing distribution wires is not directly related to the details provided, which are about different physics problems. The question on splicing wires requires additional context, while the example physics problem suggests the number of electric-field lines is proportional to charge.
Step-by-step explanation:
When considering the splicing of distribution wires, the question posed does not directly align with the general principles or guidelines of electrical engineering. In standard practice, the length that cables need to be laid out straight before splicing depends on several factors, including the type of cable, the splicing method used, and workplace safety regulations. However, the provided reference information does not contain the answer to this question. Instead, it presents various physics problems such as electric field lines, current-carrying wires, transformers, and magnetic fields. For instance, the problem about electric field lines suggests that the number of lines is proportional to the charge. Hence, if a +5 nC charge emits five electric-field lines, a +20 nC charge, which is four times greater, would emit 20 electric-field lines (option d).