which of the following statements about good experiments is true?a good experiment should hold potentially confounding variables constant between groups. none of the abovea good experiment must have an experimental group. a control group may be useful but not critical. a good experiment should only include replication if the hypothesis has never been tested before. Help me please

Which is not a characteristic of the animal kingdom? a. they include both vertebrates and invertebrates b. their skin is covered with hair or fur c. they are heterotrophs d. they are eukaryotic

Which of the following is an oxidation-reduction reaction? (pictured below)

Acar company is testing seatbelts using crash test dummies. the company finds that when cars come to a sudden stop, the crash test dummies' bodies continue to move forward. the seat belt keeps the crash test dummies from hitting the back of the seat in front of them. why do the crash test dummies' bodies continue to move forward even though the car stopped? a. the friction opposing their bodies' movement keeps them in motion. b. the inertia of their bodies keeps them in motion. c. the forward acceleration of the car keeps them in motion. d. the gravity pulling on the car keeps them in motion.