Write the following numbers using scientific notation:
`0.00000000015`

Answer

To write the number `0.00000000015` in scientific notation, we follow these steps:

### Step 1: Identify the first non-zero digit
The first non-zero digit in the number `0.00000000015` is `1`.

### Step 2: Place the decimal point after the first non-zero digit
We place the decimal point after the `1`, which gives us `1.5`.

### Step 3: Count how many places we moved the decimal point
The original decimal point is at the beginning of the number (before the zeros), and we moved it to the right until it is after the `1`. We count the number of places we moved the decimal point:
- From `0.00000000015` to `1.5`, we moved the decimal point 10 places to the right.

### Step 4: Write the number in scientific notation
In scientific notation, we express the number as:
\[ 1.5 \times 10^{-10} \]

### Final Answer
Thus, the scientific notation for `0.00000000015` is:
\[ 1.5 \times 10^{-10} \]

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