Why do you think the standards changed over time?

Which is the best predictor of the radioactive nature of an isotope? o the proton-to-electron ratio the neutron-to-proton ratio o the neutron-to-electron ratio the electron-to-proton ratio

Review multiple-concept example 7 in this chapter as an aid in solving this problem. in a fast-pitch softball game the pitcher is impressive to watch, as she delivers a pitch by rapidly whirling her arm around so that the ball in her hand moves in a circle. in one instance, the radius of the circle is 0.626 m. at one point on this circle, the ball has an angular acceleration of 66.1 rad/s2 and an angular speed of 12.6 rad/s. (a) find the magnitude of the total acceleration (centripetal plus tangential) of the ball. (b) determine the angle of the total acceleration relative to the radial direction.

7. see worksheet 1 for values of variables x1, x2 and x3 and answer the following questions: a. for each variable find the mean, median, coefficient of skewness, range and population standard deviation. b. compared to variable x1, how are the mean and median affected by extreme values (outliers) seen in x2 and x3. c. is the median or mean the better measure of location for x2 and x3? explain. d. explain the differences in the magnitudes of the skewness coefficients for the three variables. e. what is the relationship between the range and standard deviation looking across the three variables?