Answer:
idk, can I?
Step-by-step explanation:
I am pretty sure that it is C.
Answer : The substances half life in days is, 5.6 days.
Step-by-step explanation :
Half life : It is defined as the amount of time taken by a radioactive material to decay to half of its original value.
All radioactive decays follow first order kinetics.
The relation between the half-life and rate constant is:

where,
k = rate constant = 0.1235 per days
= half-life
Now put all the given values in the above formula, we get:


Thus, the substances half life in days is, 5.6 days.
<h3>
Answer:</h3>
The real solutions are -5, -4, 4, 5. There are no complex solutions.
<h3>
Step-by-step explanation:</h3>
The equation ...
... x^4 -41x^2 +400 = 0
can be factored as ...
... (x^2 -16)(x^2 -25) = 0
... (x -4)(x +4)(x -5)(x +5) = 0
So, all roots are real and are ...
... x ∈ {-5, -4, 4, 5}
_____
These are the values of x that make the factors zero.