If g is the geometric mean of 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, then which one of the following is correct?

What is the mean deviation of first 10 even natural numbers?

If $\rm \displaystyle \sum_{i = 1}^{10}x_i = 110$ and $\rm \displaystyle \sum_{i = 1}^{10}x_i^2 = 1540$  then what is the variance?

If M is the mean of n observations x₁ - k, x₂ - k, x₃ - k, _ _ _, x_n - k, where k is any real number, then what is the mean of x₁, x₂, x₃, _ _ _, x_n?