What is the best tool for calligraphy when you dont have the ink?

Natural minor half steps between scale degrees 3 and 4; 7 and 8 harmonic minor half steps between scale degrees 2 and 3; 5 and 6 ascending melodic minor half steps between scale degrees 2 and 3; 5 and 6; 7 and 8 major half steps between scale degrees 2 and 3; 7 and 8

4/5 of a number is 64 find the number

What gothic cathedral feature is pictured here