What system works with the circulatory system to provide oxygen to cells? Integumentary System
Respiratory System
Skeletal System
Digestive System

When george started his current job, his employer told him that at the end of the first year, he would receive two vacation days. after each year worked, his number of vacation days will double up to five work weeks (25days) of payed vacation. how many vacation days will he have in 4 years