An aircraft acceleration from 100m/s to 300m/s in 100 s what is acceleration

A2k pendulum has a speed of 1 m/s at a height of 1/2 meter

Henry, whose mass is 95 kg, stands on a bathroom scale in an elevator. the scale reads 830 n for the first 2.4 s after the elevator starts moving, then 930 n for the next 2.4 s. part a what is the elevator's speed 4.8 s after starting? express your answer with the appropriate units.

In an experiment, how can i change human errors? be specific.