In on painting, alberti claimed that a truly beautiful work must have both:

I believe the correct answer is proportion and perspective.

Leon Battista Alberti was an epitome of Renaissance Man – he was a humanist author, mathematician, architect, poet, priest, linguist and philosopher. In his works “Della pittura” and “De statua”, Alberti stated that beauty is harmony, found in proportion and perspective.

lithograph is created by etching the flat surface of a print.

cad, or computer-aided design and drafting (cadd), is a software for design and technical documentation, which is an automated process as opposed to the manual drawing of plans. this gives a person an advance in making plans as an architect in a short period of time. one who can render plans through this software will gain a skill that is better than one who makes plans manually. this is a skill some companies look for in an employee.