Answer:
A) ≥ 325Kpa
B) ( 265 < Pe < 325 ) Kpa 
C) (94 < Pe < 265 )Kpa
D)  Pe < 94 Kpa
Explanation:
Given data :
A large Tank : Pressures are at 400kPa and 450 K 
Throat area = 4cm^2 ,  exit area = 5cm^2
<u>a) Determine the range of back pressures that the flow will be entirely subsonic</u>
The range of flow of back pressures that will make the flow entirely subsonic 
will be ≥ 325Kpa
attached below is the detailed solution 
<u>B) Have a shock wave</u> 
The range of back pressures for there to be shock wave inside the nozzle 
= ( 265 < Pe < 325 ) Kpa 
attached below is a detailed solution
C) Have oblique shocks outside the exit 
= (94 < Pe < 265 )Kpa
D) Have supersonic expansion waves outside the exit 
= Pe < 94 Kpa
 
        
             
        
        
        
The answer is C, has negative acceleration.
        
                    
             
        
        
        
Answer:
50 kg
Explanation:
Given,
Force ( F ) = 100 N
Acceleration ( a ) = 2 m/s^2
To find : Mass ( m ) = ?
Formula : -
F = ma
m = F / a
 = 100 / 2
m = 50 kg
Therefore, the mass of the object is 50 kg.
 
        
             
        
        
        
The best answer to the question that is being stated above would be the first choice. To disprove the claims of the student that you need more protons to have more reactivity, then you proceed to compare the reactivities of lithium (Li) and krypton (Kr). Krypton has more protons than Lithium, but it is less reactive because it is a noble gas.
        
             
        
        
        
Answer:
hypothalamus
Explanation:
The hypothalamus is known as the master switchboard because it's the part of the brain that controls the endocrine system. The pituitary gland, which hangs by a thin stalk from the hypothalamus, is called the master gland of the body because it regulates the activity of the endocrine glands.