A certain radioactive substance decays by 2.4% each year. Find the half-life

i think c. but don't trust it.

step-by-step explanation:

c.

step-by-step explanation:

substitution for (0,1)

y=x^2+4x+1

1=0^2+4(x)0+1

1=0+4(x)0+1

1=4(x)0+1

1=0+1

1=1

substitution for (-3,-2)

y=x+1

-2=-3+1

-2=-2

1.) 21

2.) 0.453

3.) 1.5

4.) 48

5.) $ 22

step-by-step explanation: