When writing numbers in base 10, we only allow coefficients of 0 through 9. why is that?

Aline on the wall and a line on the floor are skew. always, sometimes, or never?

The number of potato chips in a bag is normally distributed with a mean of 71 and a standard deviation of 2. approximately what percent of bags contain between 69 and 73 potato chips? approximately 68% approximately 71% approximately 95% approximately 99.7%

What is the distance between the points (2 -3) and (-6 4) on the coordinate plane