ElectricPavlov

Wow.... that didn't translate very well !

If you meant  sqrt (3/8) = sqrt3/sqrt8 = sqrt3/sqrt(4 x 2) = sqrt3/ (2*sqrt2)

sqrt(3) / 2 sqrt(2)   multiply by  sqrt2/sqrt2

sqrt(6)/4

Let 'x' equal time for mega train

Slower train time is  x + 2.5

90 km/hr * x hr   = Distance = (x+2.5)hr * 50 km/hr

90x =(x+2.5)50

90x = 50x + 125

40x = 125

x = 125/40 = 3 5/40 hr = 3 hours 7.5 min

3  5/40 hr  *  (90km/hr) = 281.25 km apart

Amen!!!

Yes, you will.  Despite ALL recent medical advances, MORTALITY is STILL  100%.

How many half lives to get to 6.25%

   100%

1  50%

2  25%

3  12.5%

4    6.25%       4 half lives

Another way   1/2^n = .0625     

Take the log of both side

n log 1/2  = log .0625

n = log (.0625 ) / log (1/2) = 4  half lives

4 half lives x 1.1 billion yrs/halflife = 4.4 billion years old

28 x 1/10 =  28/10 = 2.8

Depends   4/ (2/3)  =  12/2 = 6

(4/2)/3  = 2/3

Potential Energy = m g h      m in kg    g=9.81 N/kg   h in meters

.7kg x 9.81 N/kg x 1.5m = 10.3 N-M = 10.3 j

Can't answer A without more information or a diagram

B  E is midpoint of CD   if CD is 24 then midpoint is 1/2 of this so CE is 12