Test Preparation on IBPS RRB Prelims Test series-1

What should come in place of question mark (?) in the following series based on the above arrangement?

How many such pair of numbers are there in the given number “46579739” (Both backward and forward) same as far as according to numeric series?

If it is possible to make only one meaningful word with the 1st ,2nd , 4th and 7th letters of the word ‘ECUADOR’ which would be the second letter of the word from the right? If more than one such word can be formed give ‘Y’ as the answer. If no such word can be formed, give ‘Z’ as your answer.