Which of the following indicates that only a physical change has taken place?

Which element is used in photosynthesis found in atmosphere and fixed by bacteria?

Some plants rely on the wind to reproduce an example is it’s important for plants to use the forces of nature to reproduce because 1. 1a white tuft of dandelion seeds 2a spiked burrs surrounding seeds 3a hard shell on a walnut? 2. 1b require pollination to reproduce 2b reproduce only asexually 3b cannot move about freely?

Darrel conducted an experiment with the following procedure: fill two cups with ice water. place an uninflated balloon snuggly onto your left index finger. blow a little air into an identical balloon, and place it onto your right index finger. place both fingers into the cups of ice water. darrel noticed that his right finger felt warmer in the ice water than did his left finger. which of the following does the experiment show? a. air is a good radiator of heat. b. air is a good insulator of heat. c. air is a good conductor of heat. d. air is a good convector of heat.