If tina starts out at 10 m/s, and in 10 seconds up to 20 m/s, what is her acceleration?

Anybody wanna ? (picture included? )

World class speed skaters can skate a 3,000-m course in about 4 minutes.what is their average speed for this course? a. 12.5 m/sb. 1.33 m/sc. 1.25 m/sd. 13.3 m/s

What happens to an isotope during radioactive decay?