Mechanics(physics) question

Hi! I was going through a textbook and came across this question.

There are two particles A and B. A is left(u=0) at a height, anđ after three seconds, B is projected downward with an initial velocity of 3 meters per second. If the two particles hit the ground simultaneously, find:
-The time taken for each particle to hit the ground.
-The distance travelled by the two particles. ie the height above the ground.

Please show workings and gibe explanation.
Note: calculus is allowed.

Aceix.
There are two particles A and B. A is left(u=0) at a height, anđ after three seconds, B is projected downward with an initial velocity of 3 meters per second.
This is very poorly worded. Here's my interpretation:
Ah(t) = -gt^2 + a
Bh(t) = (t < 3) ? (a) : (-g(t - 3)^2 - 3(t - 3) + a)

The question seems to imply that the projectiles are starting from the same position, in which case there's no solution.
That is just it. But how do you know there is no solution?

Aceix.
After 3 s, projectile A will be falling faster than 44 m/s. Projectile B would need to be thrown down even faster than that to ever be able to catch up with A.
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Thanks.

Aceix.
It is poorly worded, but I understood it to mean that particle A starts at v0=0.

Which would mean that the particles can impact the surface at any time you choose after t=3, assuming constant acceleration (-g).

PS. It really does help to draw a picture to see what stuff you are missing. I suspect that there is something else missing from the question, maybe from an assumption given in a previous question.

[edit] Oops! Thanks helios!
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Hello folks!!! Back with a question, but a mistitled one(electronics).
Check the links below.
The pic with the transistor, what happens when the circuit is closed? And how does the parallel connection of the capacitor and the resistor affect the circuit? Please explain, and some equations would also help. The transistor is an npn bjt.
The pic with the three bulbs, what happens to each of them when current flows. Why?

http://i1380.photobucket.com/albums/ah199/Aceix/Mobile%20Uploads/th_UC_Photo_0_zpsb645ddd5.jpg
http://i1380.photobucket.com/albums/ah199/Aceix/Mobile%20Uploads/th_UC_Photo_0_zpsb607b698.jpg

Aceix.
¿why don't you try to do your own homework?

for the pic with the transistor, ¿what is limiting the current to the base?

for the three bulbs, just develop the nodal analysis taking into account the 0.6V of the diode.
The diode also indicates the direction of the current, so if you get a negative value it would be the same as open circuit, and it simplifies to two sources and two resistors.
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