Answer:
35 years
Step-by-step explanation:
The proportion p that remains after y years is ...
p = (1/2)^(y/5.27)
In order for 1/100 to remain (the level decays from 100 times to 1 times), we have ...
.01 = .5^(y/5.27)
log(0.01) = y/5.27·log(0.5) . . . take logs
y = 5.27·log(0.01)/log(0.5) ≈ 35.01 ≈ 35 . . . . years
Answer:
Step-by-step expla2nation:
Answer:
A
Step-by-step explanation:
The velocity of a moving body is given by the equation:

Is the velocity is <em>positive </em>(v>0), then our object will be moving <em>forwards</em>.
And if the velocity is negative (v<0), then our object will be moving <em>backwards</em>.
We want to find between which interval(s) is the object moving backwards. Hence, the second condition. Therefore:

By substitution:

Solve. To do so, we can first solve for <em>t</em> and then test values. By factoring:

Zero Product Property:

Now, by testing values for t<1, 1<t<4, and t>4, we see that:

So, the (only) interval for which <em>v</em> is <0 is the second interval: 1<t<4.
Hence, our answer is A.
B is the answer
just like the picture
( T' is not exact. it just shows the reflection)
Step 1. Simplify 10/3b to 10b/3
12/5(10b/3 + 15/4)
Step 2. Distribute
8b + 9