Atechnique for classifying problem areas according to degree of importance, and focusing attention on the most important problem areas is referred to as:

a. quality circles
b. quality assurance
c. brainstorming
d. pareto analysis
e. cause-and-effect analysis

D

Step-by-step explanation:

Pareto analysis is a technique for focusing attention on the most important problem areas.

the one on the bottom left

step-by-step explanation:

all of the other ones have a specific pattern

check the picture below.

well, the angle at the vertex d is clearly not a right-angle, let's check for the one at the vertex f which does look like,   however if it's indeed, that means ef is perpendicular to df, in which case their slopes will be negative reciprocal of each other.

so the negative reciprocal of the slope of ef is 1, however the slope of df is not 1, is 1/2, so nope, they're not perpendicular lines.