Answer: 4 years
Step-by-step explanation:
A(0) has to be amount at start. Assume that's 5mg
Then A(t) = 5×(0.5)^(0.25t) = 5×2^(-t/4),
(also known as 5 exp(-λ t) with λ = ln(2)/4, incidentally).
We need to such that A(t) = 2.5mg, or 2^(-t/4) is 1/2, which happens when -t/4 is -1, or t is 4.
 
        
             
        
        
        
Answer:
The graph in the attached figure
Step-by-step explanation:
we have

This is the equation of the line
To graph a line we need two points
<em>Find the intercepts</em>
1) The y-intercept is the value of y when the value of x is equal to zero
For x=0


The y-intercept is the point (0,3)
2) The x-intercept is the value of x when the value of y is equal to zero
For y=0


The x-intercept is the point (-1.5,0)
To draw the graph of the line plot the intercepts and join the points
using a graphing tool
see the attached figure
 
        
             
        
        
        
Answer:
Last point is at (7,-3)
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer:
9
Step-by-step explanation:
I think what they are asking is to subtract the 3 tokens from 21 tokens he already has giving us 18. and since it says "Twice the number of tokens" I'm assuming you divide 2 from 18 giving you 9 tokens.