Anegative ion is (larger/smaller) than its parent atom

Which device uses ac current to operate?

What is the acceleration of a spaceship that is initially at rest and then speeds up to 220 m/s in 20 seconds

The force acting on a beam was measured under the same operating conditions and a sample of 5 data points was collected. this process was repeated by 3 observers. the pooled standard deviations of these 3 data sets was 1.21. determine the true mean force using all pooled data (with a 95% probability). the result should look like this: true mean = mean +/- margin of error