can u help me in problem 2 plz
Think of the vectors as of simple 7 bit binary vectors! Don't be confused because it contains 2's and 5's instead of 0's and 1's. So get a standard 7 bit vector like unsigned(6 downto 0), start with the value 0 for this vector and just increment it until 127 (all 1's). For your desired output signal, you look at this counting vector: each 0 is being output as 2, each 1 is being output as 5. That's it.