Initial volume of water is 155 mL. Convert the mass of iron and lead into volume using density values as follows:
d=\frac{m}{V}
Here, d is density, m is mass and V is volume of objects
volume of piece of iron can be calculated as:
V=\frac{m}{d}=\frac{15 g}{7.86 g/mL}=1.90 mL
Similarly, volume of lead can be calculated as:
V=\frac{m}{d}=\frac{20 g}{11.3g/mL}=1.77 mL
To calculate the final volume of water, volume of both iron and lead should be added to the initial volume of water.
V_{final}=V_{initial}+V_{iron}+V_{lead}=155 mL+1.90 mL+1.77mL=158.67 mL
Thus, new water level in milliliters will be 158.67 mL.
