1. If the mean of the numbers \(x_1, x_2, x_3, x_4, ..., x_n\) is \(\bar{x}\), then the value of \((x_1 - \bar{x}) + (x_2 - \bar{x}) + (x_3 - \bar{x}) + ... + (x_n - \bar{x})\) will be —

(a) 0 (b) 1 (c) 3 (d) 5

2. If the mean of \(x_1, x_2, x_3, ....., x_n\) is \(\bar{x}\), then the mean of \(x_1 + k, x_2 + k, x_3 + k, ....., x_n + k\) will be _____.