Acertain type of thread is manufactured with a mean tensile strength of 78.8 kilograms and a standard deviation of 7.2 kilograms. how is the variance of the sample mean changed when the sample size is (a) increased from 64 to 324? (b) decreased from 256 to 81?

Which branches of natural science include the study of an organism that lived 10 million years ago

The uniform slender bar rests on a smooth horizon- tal surface when a force f is applied normal to the bar at point a. point a is observed to have an initial acceleration aa of 20 m/s2, and the bar has a corre- sponding angular acceleration of 18 rad /s2. deter- mine the distance b.

The electric potential a distance r from a small charge is proportional to what power of the distance from the charge? a. r^-1 b. r c. r^-2 d. r^2