List and describe the four anatomical landmarks where body fat is measured using skinfold calipers

the triceps: halfway between the shoulder and the tip of the elbow on the posterior surface of the upper arm; the biceps: halfway between the bend of the elbow and the top of the shoulder on the anterior surface of the arm; the subscapula: below the shoulder blade on the posterior side of the torso; the supra-iliac: just above the iliac crest (the protrusion of the hipbone) on the anterior surface of the torso