Variance is the average of the squared deviations from the arithmetic mean. The standard deviation is a square root from variance value. The standard deviation is a measure of the variability of values around the mean and is meant to be used with values that are normally distributed (e.g., follow a normal curve).
This integrated the seat belts and airbag into a restraint system, rather than the airbag being considered an alternative to the seat belt. In 1987, the Porsche 944 turbo became the first car to have driver and passenger airbags as standard equipment. The Porsche 944 and 944S had this as an available option. The same year also saw the first airbag in a Japanese car, the Honda Legend.
Eventually, the chips were mass-produced for home consumption, but since they were stored in barrels or tins, they quickly went stale. Then, in the 1920s, Laura Scudder invented the airtight bag by ironing together two pieces of waxed paper, thus keeping the chips fresh longer. Today, chips are packaged in plastic or foil bags or cardboard containers and come in a variety of flavors, including sour cream and onion, barbecue, and salt and vinegar.