In which quadrant does the point(9, -2) lie

In which quadrant does the point(1, 5) lie

In which quadrant does the point(-4, -7) lie

 If μ_r be the rth order central­moment of a population μ₀ , μ₁  and μ₂  are : (where, σ = standard deviation)

If x is a continuous random variable with p.d.f.

ƒ(x) = 1/√2∏ exp (-x²/2), -∞ < x < ∞

and y is defined as y = x+1, then E(y) equals:

If a variable has three values  ­k, 0 and 3k with corresponding frequencies as 3k, 2k and k respectively, then the value of coefficient of skewness b₁  is :