A physical change is basically a body change so like if a crayon is solid then sits in the sun for a long time it melts away that’s a physical change because it changes its physical appearance
        
                    
             
        
        
        
Explanation:
a barometer is one of the most common instrument used for weather forecasting and measuring tornadoes.
 
        
             
        
        
        
Distention from accumulating gas and fluid impede venous return, leading to bowel wall ischemia.
<u>Explanation:</u>
When the bowel lumen is obstructed, the gases and fuids starts accumulating as a repose to the obstruction. The accumulated fluid and gases results in the swelling or enlargement. This will result in the production of electrolytes and water inside the mumen that is in obstruction. The wall of the bowle will also enlarge and becomes swollen. 
As more and more fluid and gas gets accumulated in the bowel, the bowel wall will be enlarged and as there is an increase in the pressure due to this accumulation, the fluid starts to leak from the wall. This will enter peritoneum and necrosis. This will result in an acute emergency when it becomes serious. 
 
        
             
        
        
        
Answer:
D. A cyanobacterium
Explanation:
Cyanobacteria have gas vacuoles, thykaloid membranes and carboxysomes
 
        
             
        
        
        
Humans get D vitamin from sunlight. the plants perform photosynthesis and grow , we eat those fruits and vegetables grown in the plants. so indirectly we humans and other animals are benifitted from sun sunlight . flesh eating animals eat herbivores animala so they are also benifitted