The options are;
a. V2 equals 2V1.
b. V2 equals (V1)/2.
c. V2 equals V1.
d. V2 equals (V1)/4.
e. V2 equals 4V1. 
Answer:
Option A: V2 equals 2V1
Explanation:
Since the flow is steady, then we can say;
mass flow rate at input = mass flow rate at output. 
Formula for mass flow rate is;
m' = ρVA
Thus;
At input;
m'1 = ρ1•V1•A1
At output;
m'2 = ρ2•V2•A2
So, m'1 = m'2
Now, we are told that the density of the fluid decreases to half its initial value. 
Thus; ρ2 = (ρ1)/2
Since m'1 = m'2, then;
ρ1•V1•A1 = (ρ1)/2•V2•A2
Now, the pipe is uniform and thus the cross section doesn't change. Thus;
A1 = A2
We now have;
ρ1•V1•A1 = (ρ1)/2•V2•A1
A1 and ρ1 will cancel out to give;
V1 = (V2)/2
Thus, V2 = 2V1
 
        
             
        
        
        
The
answer is: a. Skinner’s idea of language
<span>Skinner
was a psychologists and
one of the first behaviorists. In his language acquisition
theory, he states that language acquisition is an environmental and
social phenomenon; therefore, children acquire language through
operant conditioning, which includes stimuli control, reinforcement
(positive and aversive), and deprivation.</span>
 
        
                    
             
        
        
        
Answer:
Explanation:
#1 uses Newton's 2nd Law: F = ma so filling in:
750 = .4a and
a = 1875 m/s/s
#2 uses d = rt so
d = 12.3(25) and
d = 307.5 m
 
        
             
        
        
        
Answer:
I belive it would be the first answer choice. 
Explanation:
When the Mass is lower, the ball moves faster so it would have more kintetic energy
 
        
                    
             
        
        
        
The answer to your question is a vacuum.