Can someone solve number 6, and show your work plz

Answer:
3.9 kg
Step-by-step explanation:
total mass = (number of nails) * (mass of one nail)
total mass = 750 * 5.2 * 10^(-3) kg
total mass = 750 * 5.2 * 10^(-3) kg
total mass = 750 * 0.0052 kg
total mass = 3.9 kg