Janet wants to see whether drinking coffee will improve productivity. What is the independent variable in this experiment (cause)? A. the time drinking the coffee

B. increase productivity

C. drinking coffee or not

D. the brand of coffee

Insects, arachnids, and crustaceans  

Insects have 3 body segments. (head, thorax, abdomen)

Have a hard exoskeleton made of chitin.

Appendages be used for feeding, defense, sensory and reception.

Invertebrate phyla that obtains oxygen by using gills (marine) or air tubes (terrestrial.)

Use pincers and stingers as attack weapons to defend themselves

Characterized by having jointed legs, segmented bodies, and sometimes wings