Answer:

Step-by-step explanation:
The given expression is 

We group the constant terms on the right hand side to obtain;


We square both sides of the equation to remove the square root.


This will simplify to;


 
        
                    
             
        
        
        
Answer:

Step-by-step explanation:
we are given half-life of PO-210 and the initial mass
we want to figure out the remaining mass <u>after</u><u> </u><u>4</u><u>2</u><u>0</u><u> </u><u>days</u><u> </u>
in order to solve so we can consider the half-life formula given by

where:
- f(t) is the remaining quantity of a substance after time t has elapsed.
- a is the initial quantity of this substance.
- T is the half-life
since it halves every 140 days our T is 140 and t is 420. as the initial mass of the sample is 5 our a is 5
thus substitute:

reduce fraction:

By using calculator we acquire:

hence, the remaining sample after 420 days is 0.625 kg
 
        
             
        
        
        
Answer:
the 21st day
Step-by-step explanation:
21 is 3 and 7's least common multiple
 
        
                    
             
        
        
        
Answer:
A
Step-by-step explanation:
A. because the line of best fit has to be at best fit between the points so is a good approximation of where all the points are heading when you try to predict something. 
 
        
             
        
        
        
737 people I’m pretty sure