Notice u/s 148

What is the escaped amount as per 148 notice? If it is below 1 lac, then notice shall not be valid as 4 years have elapsed from A/Y  09-10. Otherwise, it shall be valid as notice has been served within 6 years. 

As stated in the 148 notice you will be required to furnish the return for a/y 09-10. But notice u/s 143(2) will not be valid, provided return was filed on time as time limit  is 6 months from end of F/Y. 142(1) notice is also not valid as 3 years have elapsed from p/y of which books are sought to be produced.