Answer: A closed circulatory system and an excretory system consisting of tubular nephridia
Explanation:
 
        
             
        
        
        
Answer:
for respiration lungs,nose
for nutrition mouth and stomach
for reproduction various reproduction organs like penis and vagina
growth -
excretory - skin(sweat) ueltra blader kidney liver 
Explanation:
 
        
             
        
        
        
The first one is C. Varying in shapes of forelimbs
The second one is B. Enable members of a phylum to survive and reproduce.
The third one is B. Deuterostome development
 
        
             
        
        
        
<u>Answer</u>:
The mass of a star can be determined by studying binary star systems.
<u>Explanation</u>:
In this system it consists of two stars, revolving round the same bary-centre. The systems having two or may say more than two are called as the multiple star system. This zone is also a habitable zone, here the water exists in the liquid form. We could have sometime seen the two stars together. They are also very capable of strengthening the terrestrial planets inside the stable orbital ranges. They have generally two orbits like P-type as well as circumbinary.  
 
        
             
        
        
        
Velocity is the speed of an object moving in a definite direction. The velocity of an object can be uniform or variable. When an object moving along a straight line at variable speed, we can Express the magnitude of its rate of motion in terms of average velocity. 
Average velocity=Initial velocity+Final velocity/2
The SI unit of velocity is m/s.