Adding or removing neutrons from the nucleus are how isotopes are created. Protons carry a positive electrical charge and they alone determine the charge of the nucleus. Adding or removing protons from the nucleus changes the charge of the nucleus and changes that atom's atomic number.
Letter d, because they are both alkali metals (group one)
40% solution of glucose is where the solution contains, by weight, 40% glucose and 60% water.
Therefore, if the total weight of the solution is 250 g,
mass of the glucose (C6H12O6) = 250 g * 40% = 100 g
mass of water (H2O) = 250 g * 60% = 150 g
Mass of water can also be calculated by subtracting the weight of glucose from the total weight of the solution:
mass of water = 250g-100g = 150g.