HELP ME please

What are that three unifying characteristics of chordates

What was new about the writing system developed by the phoenicians, and why was this important to the growth of knowledge and spread of ideas?

Examine this list of events that took place in china during the 20th century. which event or events could possibly have been a cause of the great leap forward? a. i only b. i, iii, and iv c. i and iii d. iii and iv