Answer:
false
Explanation:
it cant defined the messy and clean states
The two different isotopes have weights :
w1 = 78.918 amu
w2 = 80.916 amu
average weight w3 = 79.903 amu
The mixing of two components can be modeled as
let the fraction of w1 be 'x'
hence 
now this is a linear equation in 'x'. Substituting the values we get
x = 0.507
hence the percentage of Br79 = 50.7% and the percentage of BR81 = 49.3%
Given that,
Distance, d = 10700 km
Time taken by the airplane to complete the destination, t = 12 hours
We need to find the speed of the airplane. It is equal to the total distance covered divided by total time taken. So,

We know that,
1 km = 1000 m
1 h = 3600 s
So,

So, the speed of the airplane is 891.66 km/h or 247.68 m/s.
Answer:
Mechanical
Explanation:
The tank is at rest. And energy of any substance at rest is known as potential energy.
Now, in forms of energy, potential energy is a type of mechanical energy.
Thus, the correct option is mechanical Energy.
If you're referring to the different colors that usually occur at the tip of missles, rockets and some other aircraft, it either a) signifies the end of a particular plate of metal, fabricated specifically to be for the nose. Sometimes these can even be a different alloy or metal all together. or b) this shows where the curved surface begins, so in the case of damage or imperfections due to wear, they can be repaired and measured more easily. The shape of the nose is extremely important for smooth flight, and a dent or bump formed on it can make the aircraft unstable. If you can measure from where the curve starts by the difference in color, it makes repairing or re-fabricating the part much easier. Many of these curves aren't as simple as they appear.