Mark:
TOILET PAPER
Without having done any calculations, I'll say a parabola

(until the paper runs out; then it's a horizontal line).
Yup, I reckon it could be so described.
For every revolution of the toilet roll the height of the pen drops by the thickness of the toilet paper left on the floor behind it. If this was the only thing you had to think about, the figure would be a straight line, slanting towards the floor. But each revolution decreases the diameter of the toilet roll as well. So each revolution takes less distance along the floor. So for each revolution the pen drops the same amount in shorter and shorter distances. The final figure will be a curve of gradually increasing steepness as the roll gets closer to the end.
Ralph:
Balloon: the balloons can only travel on and with the air current.
Coffee: Leaving the coffee on the table undisturbed would allow the heat to stay longer. Blowing on it will only cool the surface briefly. Using the plastic spoon will allow the temperature to be altered throughout the cup there for it would cool quicker.
I could not have put it better.
Mark:
BALLOON
A boat is in water which provides friction to keep the wind from turning the boat/sail so that it travels parallel to the wind.
A balloon has no such medium to provide that friction; so the wind will just rotate the balloon and force it to travel parallel to the wind.
You are absolutely right, the answer should be obvious to anyone who's ever tried to sail a flat-bottomed boat. The reason a ship can sail across, or even into the wind, is not because of its sails, but because of its keel. When the sails of a ship catch the wind, they are pushed essentially in the direction of the wind. But the ship's keel provides resistance against this force, and so the force is sort of "redirected" in the direction that the captain has pointed his vessel. (There are other effects as well, but this is the basic principle.) In the case of the balloon, however, since there is no keel, the only real effect the three sails would have had was to make the balloon slowly rotate as it was blown along.
COFFEE
(a) is out.
(b) would cool the surface, but convection would cause the cooled surface liquid to mix with the warmer liquid below.
(c) would bring more of the liquid in contact with the air (aids convection), but also adds (negligible) heat due to friction. A metal spoon would probably be better as it would act as a heat sink.
I'll go with (c) since the aid to the natural convection should be beneficial.
Ralph:
CHOO CHOO! Mark would be wrong in the assumption. He only has a better chance of catching the west bound train. His odds are 2:1 on catching the west bound.
to catch the east bound he only has a 20 minute gap but to catch the west bound he has a 40 minute gap.
40 min : 20 min
2:1
Spot on, which is what Mark thought as well, " No. The interval before the westbound train is twice the interval before the eastbound train."
Ralph:
True and False:
1. False - they don't want to drown
2. True
3. True
4. False
5. True

but what the hell do I know - About 80% by the look of things.
Mark:
1. false (guessing that they do it to avoid drowning)
2. true (guessing that the heart gets in the way of the left lung)
3. true (seems I have to trim the fingernails a bit more often)
4. false (seems I've had good eggs float and sink)
5. ?
How many people, one at a time, would you need to ask in order to have at least a 50% chance of finding two with the same day and month of birth
Why
7x12 perhaps?
FACT: Aristotle thought heavy objects should go faster under gravity and Galileo said everything falls at the same rate.
You took a full coke can, an empty coke can and an half empty coke can and put them at the top of a ramp and rolled them down to see which would arrive faster.
Which can won
You can also use Sprite or Dr Pepper. :wink:
50/50 - True or False
6. There are more bones in the arm than in the leg.
True
False
7. A spider is an insect.
True
False
8. It is harmful for the eyes to watch television in the dark.
True
False
9. Our fingers have three bones while our thumb has only two.
True
False
10. All the air in the lungs gets changed with each breath.
True
False