Answer:
D
Explanation:
it doesn't matter how many protons k has all the answers have electron with the positive charge when is negative the question is trying to distract you D is the only one that would use the electrons sign correctly
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
C. The gravity on the Moon is less than the gravity on Earth.
Explanation:
The weight of Neil Armstrong changed because the gravity on the Moon is less than the gravity on earth. We can infer that the gravity on moon is one-sixth the gravity earth.
- Mass of Armstrong on earth and moon is the same. Mass is the quantity of matter contained in a substance. Since he has the same quantity of matter on earth and moon, his mass will be the same.
Weight is a function of mass and gravity on a body.
Since his weight reduced, we can infer that the gravity on the moon is lesser:
Weight = mass x gravity.
Learn more:
Weight and mass brainly.com/question/5956881
#learnwithBrainly
Is it multiple choice? If not your answers are metals, and when nonmetals react.