B positive patients can receive blood from B positive, B negative, O positive and O negative donors.
 
        
             
        
        
        
Make sure you post the picture of the tree, so I can answer.
        
             
        
        
        
Heart rate decreased suddenly and then MAP immediately fell because peripheral blood vessels were extensively vasodilated. 
Explanation:
A VO2 max test is a clinical test done in a lab and is the ‘golden standard’ for measuring the potential and cardio-respiratory endurance of athletes and bikers.
It measures the oxygen carrying capability through a graded step test which determines the average power output. The maximal oxygen uptake along with cardiorespiratory responses is measured.
As per exercise physiology, the heart rate and cardiac output increases with exercise. When the potential is less, the resistance decreases, heart rate and mean arterial pressure also decrease
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Since chemical weathering is the reaction of rocks with other chemicals, the answer should be answer D!
Hope this helps, if not, comment below please!!!
 
        
                    
             
        
        
        
Answer:
C. Prescribed forest fires promoting healthy ecosystems.
Explanation:
This is because at that particular prescription,the place must have been analysed and proved that the forest fires would create more good to ecosystems than harm.