The problem above can be solved using M1V1=M2V2  where M1 is the concentration of the concentrated, V1 is the volume of the concentrated solution, M2 is the concentration of the Dilute Solution, V2 is the Volume of the dilute solution. Hence,
(3.0 M)(V2)=(250 mL)(1.2M)
V2 (3.0)= 300
V2= 100 mL
Therefore, you need 100 mL of 3.0 M HCl to form a 250 mL of 1.2 M HCl.
        
             
        
        
        
Answer:
2 C₄H₁₀(l) + 13 O₂(g) ⇄ 8 CO₂(g) + 10 H₂O(g) 
Explanation:
When a substance burns we talk about a combustion reaction. When combustion is complete the products are carbon dioxide and water, like in this case. The equation is:
C₄H₁₀(l) + O₂(g) ⇄ CO₂(g) + H₂O(g)
First, we balance the element with the largest stoichiometric coefficient (C).
C₄H₁₀(l) + O₂(g) ⇄ 4 CO₂(g) + H₂O(g)
Then, we balance H because it is in just 1 compound on each side.
C₄H₁₀(l) + O₂(g) ⇄ 4 CO₂(g) + 5 H₂O(g)
Finally, we balance O.
C₄H₁₀(l) + 6.5 O₂(g) ⇄ 4 CO₂(g) + 5 H₂O(g)
Since we want the smallest whole numbers, we multiply all coefficients by 2.
2 C₄H₁₀(l) + 13 O₂(g) ⇄ 8 CO₂(g) + 10 H₂O(g) 
 
        
             
        
        
        
Paramecia are examples of unicellular organisms. They are protists. 
<h3>Protists</h3>
Protists are eukaryotic unicellular (single-celled) organisms that do not fit into any other category.
Paramecia are protists microorganisms generally found in aquatic habitats (e.g., a pond). 
Paramecia generally have an oblong shape and they are covered with tiny structures known as cilia (for motion).
Learn more about protists here:
brainly.com/question/12206236