When you have the bottom measurement of the triangle (base) and the height of the triangle in the center, you multiply them together and then divide by 2.
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The salt causes the water to freeze at a lower temperature. When a solute, aka salt, is introduced to the system, the freezing point is lowered. This makes the water freeze at a lower temperature.
Explanation:
A nuclear fission reaction is defined as the reaction in which a heavy nucleus splits into small nuclei along with release of energy.
The given reaction is 
Now, we balance the mass on both reactant and product side as follows.
235 + 1 =
236 = 234 + x
x = 236 -234
= 2
So, now we balance the charge on both reactant and product side as follows.
92 + 0 = 
92 = 96 - y
y = 4
Thus, we can conclude that there are 2 neutrons and 4 beta-particles are produced in the given reaction.
Therefore, reaction equation will be as follows.

X ml - <span>25% alcohol mixture
y ml - </span><span>90% alcohol mixture
x+y = 455
0.25x ml alcohol in </span>x ml of 25% alcohol mixture
0.9y ml alcohol in y ml of 90% alcohol mixture
0.75*455= 341.25 ml alcohol in 455 ml of 75% alcohol mixture
0.25x+0.9y=341.25
System of equations:
x+y = 455 /*(-0.25) ------> -0.25x-0.25y = -0.25*455
0.25x+0.9y=341.25
-0.25x-0.25y=-113.75
0.25x+0.9y=341.25 Add both equations
0.25x+0.9y-0.25x-0.25y=341.25-113.75
0.65y =227.5
y=227.5/0.65 = 350 ml of 90% alcohol mixture
x+y=455
x+355=455
x=100 ml of 25% alcohol mixture