Concave Up and Down Functions, and Inflection Points

Concave up: $(-\infty,-1)\cup(5,\infty)$

Concave up: $(-\infty,2)$

Concave up: $(2,\infty)$

Concave down: $(2,\infty)$

Concave down: $(-\infty,2)$

Concave down: $(-\infty,-1)\cup(5,\infty)$