Which one letter when placed in the blanks can be used to form a meaningful English word_ns_d_ous

werHow many meaningful English words can be made with the letters ONDE using each letter only once in each word?

Which two letter strings will complete the words below?

Select the correct sequence of letters which should come in place of blank spaces to form a meaningful word.APP _ _ R _ NCEAAEABAEECEAEDEAA

The next set of letters will be......                                      ace; bdf; ceg; dfh; ........*

How many different words can be formed using the letters of the word ‘EDUCATION‘ such that, the word always starts with the letter “D" ?