Add using a number line. − 2/5+ 4/5 drag and drop the word sum to the correct value on the number line. do

Please refer to the attached image.

-2/5, 4/5 and -2/5 + 4/5 have been marked in red in the image

The points marked on the number line are separated by a distance of 1/5.

So when you add 4/5 to -2/5 you need to move 1/5 4 times (4/5 = 4 x 1/5) towards the right to reach the SUM.

Based on this, the sum of -2/5 and 4/5 is 2/5, and has been highlighted in the image.

water molecules move throughout the solute is true.

step-by-step explanation:

that is true because it's about the dissolving process that is when solute is dissolved into solution. the water molecules moves throughout the solution. the solute molecules gets properly dissolved to form solution and gets uniformly distributed throughout the solution. it usually forms a homogeneous mixture in the solution.