What did Leonardo observe Verrocchio create for his patrons, The answer is Leonardo would have been exposed to both theoretical training and a vast range of technical skills including drafting, chemistry, metallurgy, metal working, plastic casting, leather working, mechanics and carpentry as well as the artistic skills of drawing, painting, sculpting and modelling.
I think i honestly don't know if im correct... Sorry if im wrong, but I think its because they can not be trusted.. I hope this helped if it was correct