Evaluate:
a. `(-1) times (-1) times (-1) times (-1) times (-1) times (-1) times (-1) times (-1)`
`(-1) times (-1) times (-1) times (-1) times (-1) times (-1) times (-1) times (-1)times (-1) times (-1) times (-1)`

Answer

To evaluate the expression

\[ (-1) \times (-1) \times (-1) \times (-1) \times (-1) \times (-1) \times (-1) \times (-1) \times (-1) \times (-1) \times (-1) \]

we can follow these steps:

### Step 1: Count the number of factors
First, we need to count how many times \(-1\) is being multiplied. In this case, there are 11 factors of \(-1\).

**Hint:** Count the total number of \(-1\)s in the expression.

### Step 2: Pair the factors
Next, we can pair the factors of \(-1\). Each pair of \(-1\) multiplied together gives us \(1\):

\[ (-1) \times (-1) = 1 \]

Since we have 11 factors, we can pair them up as follows:

- The first 10 \(-1\)s can be paired:
\[ (-1) \times (-1) = 1, \quad (-1) \times (-1) = 1, \quad (-1) \times (-1) = 1, \quad (-1) \times (-1) = 1 \]
This gives us 5 pairs, each resulting in \(1\).

**Hint:** Remember that two negatives make a positive.

### Step 3: Calculate the result of the pairs
After pairing, we have 5 pairs of \(-1\)s, which gives us:

\[ 1 \times 1 \times 1 \times 1 \times 1 = 1 \]

Now we have one unpaired \(-1\) left over from the original 11 factors.

**Hint:** Keep track of any unpaired factors after pairing.

### Step 4: Multiply the result by the unpaired \(-1\)
Now, we multiply the result from the pairs by the remaining \(-1\):

\[ 1 \times (-1) = -1 \]

### Final Result
Thus, the final result of the expression

\[ (-1) \times (-1) \times (-1) \times (-1) \times (-1) \times (-1) \times (-1) \times (-1) \times (-1) \times (-1) \times (-1) \]

is

\[ \boxed{-1} \]