Powering an electrical device with a battery requires a path for electricity to flow through a closed circuit, and batteries are electro-chemical devices. Given these facts, an electrical device can be powered with what device among the following options: - direct energy - electrically - broken - electroverse - hydrogen and oxygen - operated - electromagnetic energy - electro-chemical
electro-chemical

Echinoderms have a unique water vascular system with tube feet, and sea stars use hundreds of tube feet. Given these facts, sea stars use a unique water vascular system with what among the following options: - growth - a ray - feet - oxygen - porous - energy - Light - volume
feet

Plastics are made from petroleum and produce toxic waste, and plastic is a big contributor to landfill waste. Given these facts, products made from what are a big contributor to landfill waste among the following options: - burning coal - acetic acid - tin - hydrocarbons - brass - Pesticides - petroleum - recyclables
petroleum