If you are smart than try to help me out with these questions.

1. You believe that an adult animal you are examining is a vertebrate but concede that it may be an invertebrate chordate. Which of the following would ensure that you are indeed looking at a vertebrate?
Its notochord functions as an endoskeleton.
A. It is able to swim.
B. It lacks a notochord.
C. It has a dorsal hollow nerve cord.
D. It uses its pharyngeal gill slits for respiration
2. Which of the following adult animals might you find floating in the open ocean, suspension feeding using its pharyngeal gill slits?
A. an ascidian
B. a vertebrate
C. a lancelet
D. a salp
E. a sea squirt
3. Why do adult urochordates (tunicates) lack notochords, even though larval urochordates have them?
A. Larvae use notochords to aid in swimming; adults are sessile and thus no longer need notochords.
B. Larvae use notochords to organize their nervous systems; adults' nervous systems are fully developed and do not change.
C. Larvae use notochords to induce tissue differentiation; in adults, tissue is already differentiated.
D. Larvae use notochords to stiffen their bodies; in adults, the notochord is replaced by a column of bone.
4. The structure that develops into the vertebrate spinal cord is the _____.