Let A be the sum of the first 20 terms and B be the sum of the first 40 terms of the series `1^2+2.2^2+3^2+2.4^2+5^2+2.6^2+...` If `B-2A=100lambda` then `lambda` is equal to (1) 232 (2) 248 (3) 464 (4)496