Jean is doing an experiment to find out whether mold grows faster on certain types of bread. she has eight different types of bread. she places them out on the same counter. every day, jean examines each loaf of bread for signs of mold growth. she then records her observations.

which variable is jean changing in the experiment?
a.
the type of bread
b.
the type of mold
c.
the amount of time each loaf is left out
d.
the amount of light each loaf receives

Two technicians are discussing how to test a car's exhaust by holding a small piece of paper within an inch of the tailpipe mouth. technician a says that if the paper is vibrating due to a "puffing" output from the tailpipe, this signals a smoothly running engine. technician b says that if the paper is being drawn toward the tailpipe, this could indicate burned exhaust valves. who is correct? a. technician b b. both technicians a and b c. technician a d. neither technicians a or b

Which scenario describes intraspecific, indirect competition? a. a peacock defends its territory against another peacock. b. lions and hyenas compete for the same prey animals. c. a male black bear eats fish in an area of a lake, so other black bears can’t. d. different species of birds fight over spilled popcorn on the ground.

Earth takes in thermal energy from the sun in a process called . sunlight strikes earth’s surface at different angles. this angle is called the angle of . btw its