Answer:
The fixed cost at any level of activity is $48,000 while the variable cost per unit at any level of activity is $1.30
Explanation:
The total cost is a function of the fixed and variable cost. Whilst the fixed cost does not change at a certain range of activities level, the variable cost changes as the level of activities(units produced or sold). 
Using the high and low levels of activities given, let the variable cost per unit be v and the fixed cost F
for the high level,
F + 90,000v = 165,000
For the low level
F + 40,000v = 100,00
Solving both equations simultaneously,
50,000v = 65,000
v = $1.30
F + 40,000($1.30) = 100,000
F = 100,000 - 52,000
F = $48,000
 
        
             
        
        
        
Answer:
b. Debt ratio
Explanation:
The liquidity ratio includes the current ratio, quick ratio, etc
where,  
Current ratio = Total Current assets ÷ total current liabilities
And, Quick ratio = Quick assets ÷ total current liabilities  
where,  
Quick assets = Cash and cash equivalents + short-term investments + Accounts receivable (net)  
These two ratios check the liquidity of the business organization whereas debt ratio shows a relationship between the total liabilities and the total assets. It checks the leverage of the firm whether it is capable to repay the borrowed amount or not
Hence, option b is correct
 
        
             
        
        
        
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