थिस इस interesting

This is quite interesting.Do you know?First 4 alphabets ( 'a', 'b', 'c' & 'd') which are quite commonly used; do not appear anywhere in the spellings of 1 to 99 !(Letter 'd' comes for the first time in Hundred)Letters 'a', 'b' & 'c' do not appear anywhere in the spellings of 1 to 999 !(Letter 'a' comes for the first time in thousand)Letters 'b' & 'c' do not appear anywhere in the spellings of 1 to 999,999,999 !(Letter 'b' comes for the first time in Billion)And Letter 'c' does not appear anywhere in the spellings of entire English Counting