**Answer:**

**Step-by-step explanation:**

The initial population of bacteria is 800 and we know that this number is quadrupling every hour.

<u>We're going to find a function in terms of t (time) that gives us the population of bacteria at that time.</u>

Since the population is quadrupling every hour the function in terms of t (where t is expressed in hours) is:

Now we need to find the time when there will be 5,120,000 bacterias. This means **the time t when f(t) = 5,120,000**

So we have 5,120,000 =

**Therefore, the time when there will be 5,120,000 bacterias will be:**

**Answer:**

7.406

**Step-by-step explanation:**

It is 7.406 because 7x1 is 7, 4/10 is 0.4, and 6/1000 is 0.006. If you add those together, you will get 7.406.

To undo addition, you must subtract. Since we're subtracting 7 from one side, we must subtract 7 from the other side as well.

6x + 7 = 19

When we subtract 7, both sides are subtracting 7 to balance the equation.

6x = 12

Divide both sides by 6.

x = 2.

Hope this helps!

**Answer:**

11

**Step-by-step explanation:**

PC=QC=RC

3x+7=51-x

3x+x=51-7

4 x=44

x=11

**Answer:**

On the graphing calculator, use the function normCdf, where

- lower bound = -9999
- upper bound = 210
- mean = 250
- standard deviation = 46

It will result in normCdf(-9999,210,250,46) ≈ 0.192269 or 19.2269%