5. How much force is needed to stop a 1,400 kg truck pulling up to a stop light if the truck took 4 seconds to stop and was moving at 36 m/s?

Step-by-step explanation:

F=ma

F=m(dv/dt)

F=1400(-36/4)

F=-12600N (the negative sign just means the force was slowing the vehicle, the magnitude of the force is just the absolute value.

F=12600N

0.16 or 16%

step-by-step explanation:

lets take a coin for example.

if you toss it twice, it has a 1/4 chance of landing on heads both times because 1/2 * 1/2 is 1/4.

with the cards, the chance of picking dog is 0.4. having two people pick one is like picking a card twice in a row. so 0.4 * 0.4 is 0.16, or 16%