What was the major contribution the romans made to the mortar recipe and how to improve building

In what ways were berlin's songs expressions of continuity in american culture? in what ways did they signify change in american culture?

Judy pfaff’s installations combined different art forms to express her unique vision of the world. which is not an art form pfaff integrated into her installations? !

(i think my answer is a, am i correct? ) a pentagonal traffic sign is a sign. a. school crossing b. parking c. wrong way d. yield