A 10-meter banner contains 19 characters. How big is the font size and how large are the intervals?

Banners have fixed specifications. If they are too big or too small, the banner machine cannot produce them.

The most common specification, I would say the most common, is that the width of the banner is 75 ( Most manufacturers cut corners and they can only achieve about 72) and the character height is 45 cm.

The two ends of the characters should be more than 20 centimeters from both ends of the banner (excluding the size after sewing at both ends of the banner). The character spacing is 0 (CDR algorithm). The font should be large black (if it is used for arches, it is super thick black)