In one sentence, describe what the following article is about: Make sure that the space is big enough to hold your car. It will have to be at least 25% longer than the length of your car. You will also want to check for fire hydrants, yellow edges on sidewalks, or handicap signs as to why the space might be left empty. This will allow other cars behind you to drive around. Pull up next to the car in front of the empty spot. You want to be as close to the other car as possible, not more than 12 inches (30.5cm) away. Ensure that the front of your car is the same distance from the car next to you as the back of your car (don't slant your car at an angle). Your bumper should line up directly parallel to the car next to you. Start backing up slowly until your head is parallel with the wheel of the car to your right. Press on the brake and hold your car steady. Turn your steering wheel as far as it will go clockwise. Look over your left shoulder as far as you can and start backing up again. Keep backing up until you can see the front wheel of the car behind you in your right mirror. Your car should now be positioned at a 45 degree angle into the parking space. Press on your brake and steady your car. Do this while maintaining your foot on the brake. When it has moved as far as it will go, begin backing up again slowly. Glance from front to back to ensure that you are not going to bump the car in front or the car in back. If you either bump into the curb, or get too close to the car in back of you, turn the top of the wheel to the right again and pull forward slowly. Steer your car into the proper position. Leave space in front and behind to allow yourself and the other people to get out of the parking spots. If you park very far forward or back and another car parks very close to you, you will be too tight to get out of your spot, so don't forget to leave that space. If done correctly, you should leave no more than 12 inches from the curb to your car.
Summary: Find an empty parking spot. Turn your blinker on to the right. Put your car in reverse. Turn your wheel all the way counter-clockwise. Continue to back up until you are parked. Exit your vehicle.

In one sentence, describe what the following article is about: Take all of your calculated returns and add them together. Then, divide by the number of returns you are using, n, to find the mean return. This represents the average return over the time period you are measuring. Specifically, the mean, m, is calculated as follows: m =(R1+R2+...Rn)/(n). For example, imagine that you had 5 periods that had calculated returns of 0.2, -0.1, -0.3, 0.4, and 0.1. You would add these together to get 0.3 then divide by the number of periods, n, which is 5. Therefore, your mean, m, would be 0.3/5, or 0.06. For every return, Rn, a deviation, Dn, from the mean return, m, can be found. The equation for finding Dn can be expressed simply as Dn=Rn-m. Complete this calculation for all returns within the range you are measuring. Using the previous example, you would subtract your mean, 0.06, from each of the returns to get a deviation for each. These would be: D1=0.2-0.06, or 0.14 D2=-0.1-0.06, or -0.16 D3=-0.3-0.06, or -0.36 D4=0.4-0.06, or 0.34 D5=0.1-0.06, or 0.04 Your next step is to find the mean variance of the returns by summing the squared individual deviations from the mean of the returns. The equation for finding the variance, S, can be expressed as: S=(D1^2+D2^2+...Dn^2)/(n-1). Again, sum the squares of the deviations, Dn, and divide by the total number of variances minus 1, n-1, to get your mean variance. First, square your deviations from the last step. These would be, in order: 0.0196, 0.0256, 0.1296, 0.1156, 0.0016. Sum these numbers to get 0.292. Then, divide by n-1, which is 4, to get 0.073. So, S=0.073 in the example. The volatility is calculated as the square root of the variance, S. This can be calculated as V=sqrt(S). This "square root" measures the deviation of a set of returns (perhaps daily, weekly or monthly returns) from their mean. It is also called the Root Mean Square, or RMS, of the deviations from the mean return. It is also called the standard deviation of the returns. In the example, this would just be the square root of S, which is 0.073. So, V=0.270. This number has been rounded to three decimal places. You may choose to keep more decimals to be more accurate. A stock whose price varies wildly (meaning a wide variation in returns) will have a large volatility compared to a stock whose returns have a small variation. By way of comparison, for money in a bank account with a fixed interest rate, every return equals the mean (i.e., there's no deviation) and the volatility is 0.
Summary:
Find the mean return. Calculate the deviations from the mean. Find the variance. Calculate the volatility.