Укажите номера предложений, в которых инфинитив является подлежащим и переведите все предложения: 1. To produce negative electrodes iron and zink plates are used.
2. To produce negative electrodes was the first task of the engineer.
3. To work in this field of science was the task of the engineer.
4. To work successfully in this field of science the student must know the
fundamentals of electrical engineering.