Which of the following is an organ of the digestive system?
a. stomach
c. muscle cell
b. nerve tissue
d. epithelial tissue stomach

During a hot day, warm and moist air rises and cools in the atmosphere. which even would occur next on such a day? a. condensed droplets would gather to become water vapor. b. water vapor would condense into tiny droplets. c. water droplets would evaporate to form rain and snow.

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.

What did hunter gathers do to alter the environment?