Why is it difficult to study the dark ages

What was a result of the use of farming machines

If any state tribunal decides a federal question and the litigant has no further remedy within the state court system, from which of the following remedies could the litigant possibly benefit? a.a hearing by a us district courtb.a hearing by a federal court of appealsc.a hearing by the us supreme courtd.a congressional vote b, the correct one!

Who proposed the pudding model and what does it say about the structure of the atom