In order to change a 2.15 kg handcart's velocity from 1.2 m/s east to 1.8 m/s east, what's the magnitude of the impulse that
should be applied to the handcart?
a
38.7 N-s
b 12.9 N-S
2.58 N-S
d 3.87 N-s
e
1.29 N. S

Need in all of themmm only answer if you know plsssss

Astone is dropped from a cliff and falls 9.44 meters. what is the speed of the stone when it reaches the ground? a. 13.6 m/sec b. 1.39 m/sec c. 185 m/sec d. 9.80 m/sec

The radioactive isotope of lead, pb-209, decays at a rate proportional to the amount present at time t and has a half-life of 3.3 hours. if 1 gram of this isotope is present initially, how long will it take for 80% of the lead to decay? (round your answer to two decimal places.)