If the radius of a circle is doubled in length, the circumference of the circle is

The brain volumes (cm cubed) of 50 brains vary from a low of 904 cm cubed to a high of 1488 cm cubed. use the range rule of thumb to estimate the standard deviation s and compare the result to the exact standard deviation of 175.5 cm cubed, assuming the estimate is accurate if it is within 15 cm cubed

Asap! i'm not good math and i'm lost.

The graph of f(x) = |x| is transformed to g(x) = |x + 11| - 7. on which interval is the function decreasing?