The half-life of Iodine-131 is approximately 8 days. Find the amount of Iodine-131 left from a 42 gram sample after 16 days. 1) 0.0006 grams

2) 21 grams

3) 10.5 grams

4) 34 grams

Step-by-step explanation:

The formula for this is

where

N is the amount of the element left after a certain amount of time (for us it is measured in days),

N₀ is the initial amount of the element in grams,

t is the number of days gone by, and

H is the half life of the element. Filling in:

which simplifies a bit to

and a bit more to

N = 42(.25) which gives us a remaining amount of

N = 10.5

infinitely many solutions

step-by-step explanation:

we have been given the equation;

2(2x + 3) = -4 + 2(2x + 5)

we need to determine the value of x.

2(2x + 3), we expand this expression to obtain 4x + 6

similarly 2(2x + 5) will become 4x + 10

now we have;

4x + 6 = -4 + 4x + 10

4x + 6 = 4x + 10 - 4

4x + 6 = 4x + 6

the expression on the left hand side is identical to the one on the right hand side. therefore, we are looking at just a single straight line whose equation is;

y = 4x + 6

consequently, we shall have infinitely many solutions