설명
Pulleys are simple machines used to lift and move loads. Builders use pulley systems to lift tools or materials up high and elevators go up and down with the help of pulleys. Kids will learn how pulleys make work easier and how they are often part of complex machines.
책 세부 정보
형식
전자책
페이지
25 페이지
언어
영어
출판됨
8월 1, 2009
출판사
Bellwether Media
판본
판본 2개
ISBN-10
1612115047
ISBN-13
9781612115047