Gretchen wants to run a test to discover whether glass, copper, wood, or plastic conduct electricity. She sets up a circuit connecting a battery to a light bulb, with a small gap she will use to test the conductivity of the different substances. One at a time, she connects the circuit with the chosen test material, and records whether or not the light bulb comes on. The variables in this experiment are

A) The wood and glass.
B) The copper and plastic.
C) The light bulb and battery.
D) The plastic, wood, copper, and glass.

Tara sees a commercial for a brand of pills that promise to boost energy and people perform better in work and school. as people in the commercial talk about how much better they feel when taking the pill, tara notices a message on the bottom of the screen that reads, "this pill is not approved by doctors and has not been tested in controlled experiments." what is the best conclusion that tara should make about the commercial? it is making scientific claims based on subjective observations. it is making scientific claims based on opinions instead of pseudoscientific facts. it is making pseudoscientific claims based on objective observations. it is making pseudoscientific claims based on opinions instead of scientific facts.

It is believed that europa, one of jupiter’s moons has an ocean beneath its surface. based on how earth’s oceans and atmosphere are believed to have formed, what can be said about europa’s supposed ocean? the arrival of in the early days of europa’s existence could have formed its ocean. it is likely that the water experienced , similar to earth. it is also possible that this water is retained beneath europa’s surface and in its atmosphere due to europa’s .

Restriction enzymes are used in making recombinant dna. describe the role restriction enzymes perform when constructing recombinant dna.