A twice-differentiable function g satisfies the following for all real x:
• g′(x)<0 when −4<x<−1 or x>5, and g′(x)>0 elsewhere.
• g′′(x)>0 when x<−4 or x>2, and g′′(x)<0 on −4<x<2.
Identify every open interval on which g is increasing and concave down at the same time.