THAT was FUNNY.....I sent it out to a few folks too !  

Hmmmm.... I do NOT know if any of these calculations are correct, but here is my try

v = vo + at      (1)

t=10.5 sec

+a = 9.81 m/s^2

-a = air resistance = 1.5 m/s^2  x  v m/s  /  7.5 m/s = .2 v      (2)

Substituting into equation (1):

v = 0 + (9.81 - .2v)(10.5)  = 103 - 2.1v

v+2.1v = 103

3.1v = 103     or v  = 33.225 m/s   at 10.5 seconds

Now let's find the height

x = xo + vot + 1/2 at^2           xo and vo are zero for this application, so we are left with

x = 1/2 a t^2     

x = 1/2 (9.81 - .2(33.225))(10.5)^2  = 174.47 m   (??)

Terminal velocity is where air resistance EQUALS gravity

1.5m/s^2 x v m/s / 7.5m/s  = 9.81 m/s^2

.2 v = 9.81

v(terminal) = 9.81 /  .2  = 49.05  m/s

I am VERY unsure of ANY of this ...I hope someone will confirm it or laugh out loud at my answers!  (I'm almost afraid to post it!)

Holy Cow!!!!   That is incredible....don't know what you are going to DO with it, but it is pretty cool.

If 'percentage added' means compunded annually

FV=PV(1+i)^n    FV= Future Value  PV=Present Value   i =decimal interest (.09)   n = number of periods (3)

FV=650(1.09)^3=841.77

If it is just simple interest    650(.09)(3)+ 650 = 825.50

SUBTRACTING a NEGATIVE makes it a POSITIVE :

-7 - (-9) = -7 + 9 = 9-7= 2

20 cents.

rate x time = distance

First distance = 3/4                    Second Distance = 1/4         (the two legs of your commute)

r (t) = 3/4                                     r(2t) = 1/4                          (the second leg takes twice as long)

r (1) = 3/4                                     r(2) = 1/4

r = 3/4  = 6/8                                r = 1/8

So you can see the first-leg train is SIX times faster than the second-leg train

so the fair for the second one should be 1/6th the first one 

1/6 x 1.20 = 20 cents

I trust you realize that 3/3 = 1

so 4/3 x 3/3 = 4/3    ( or   12/9  which simplfies to 4/3)

A little ambiguous (see thread from a couple of days ago re : 48/2(9+3)

(2/3)^2   x   3/4 =  4/9  x 3/4 = 1/3

2/(3^2)   x    3/4 =  2/9 x 3/4 = 1/6

(2/3)^(2*3/4) 2/3 ^(6/4) = .54433

etc.....

Not POSITIVE, but I think the answer is given in radians/sec

281. 718 R/sec   =   44.83 Hz

Just a FYI:

Before we go too far down this thread, a little clarification.....this is generally referrd to as Euler's NUMBER   ..... Euler's CONSTANT is something else. 

Happy Hanukkah !   ....  or  Merry Christmas Eve.....   Or Kwanzaa (26th)....

.....or just "Have a nice day"