What is another way to name angle ABC?

What is the standard deviation of the following data set rounded to the nearest tenth? 3, 17, 18, 15, 12, 21, 9

Jason went to an arcade to play video games. he paid $2 for every 11 tokens he bought. he spent a total of $16 on tokens. which equation can be used to determine,t, the number lf tokens jason bought

These tables represent a quadratic function with a vertex at (0, -1). what is the average rate of change for the interval from x = 9 to x = 10?