Answer:
A.
Mass per page = mass of book / number of pages
Mass per page = 2.5kg / 500 pages = 0.005kg
B.
Mass per page = mass of book / number of pages
Total mass = 2.5kg = 2,500grams = 2,500,000mili grams
Mass per page = 2500000mg / 500 pages = 5000mg