Answer:
a
Step-by-step explanation:
11 books;
157 books - 102 books = 55 books (donated)
55 books divided by those 5 months in between is 11 books
A kilogram is 100 grams. We can convert 1/5 kg into 1/5 of 100g... or 20g
3/5 g < 20 g
1/5 of a kilogram is heavier.