There are three specifications in total:    

Small trumpet: 3 cm diameter, 0.32 yuan/piece 

Medium: 4 cm diameter, 0.35 yuan/piece

Large: 5 cm diameter, 0.65 yuan/piece

Small trumpet: 3 cm diameter, 0.32 yuan/piece 

Medium: 4 cm diameter, 0.35 yuan/piece

Large: 5 cm diameter, 0.65 yuan/piece

Commonly used photo size resolutions and pixels
( 1 inch 1R) 2.6×3.7(cm)
"( 2英寸 2R) 6.3×8.9(厘米)" can be translated as "(2 inches 2R) 6.3×8.9(centimeters)".
5×3.5 ( 5英寸 3R) 12.70×8.89 (厘米) 1200x840以上 100万像素" Translation: "5×3.5 ( 5-inch 3R) 12.70×8.89 (centimeters) 1200x840 or higher 1 million pixels
6×4 ( 6 inches 4R) 15.24×10.16 (centimeters) 1440x960 or higher 1.3 million pixels
7×5 ( 7 inches 5R) 17.78×12.70 (centimeters) 1680x1200 and above 2 million pixels
8×6 ( 8 inches 6R) 20.32×15.24 (centimeters) 1920x1440 and above 3 million pixels

9×6 ( 9 inches 6R) 22.86×15.24 (centimeters) 1920x1440 and above 3 million pixels
10×8 (10 inches 8R) 25.40×20.32 (centimeters) 2400x1920 or higher 4 million pixels
12×10 (12 inches) 30.48×25.40 (centimeters) 2500x2000 or more 5 million pixels
14×12 (14 inches) 35.56×30.48 (centimeters)
15×10 (15 inches) 38.10×25.40 (centimeters) 3000x2000 6 million pixels

16×12 (16 inches) 40.64×30.48 (centimeters)
18×12 (18 inches) 45.72×30.48 (centimeters)