You are presented with the question "using a gasoline engine requires what?" and the following answer choices:  - electricity  - no ignition  - carbon dioxide  - easy ignition  - difficult ignition  - no gasoline  - hydrogen and oxygen  - adding heat  Now knowing that using a gasoline engine requires burning gasoline and gasoline ignites easily and burns vigorously, choose the best answer.
easy ignition

You are presented with the question "In the male orgasm, where is sperm propelled from?" and the following answer choices:  - seeds  - pollen  - distance  - organ  - sensory neurons  - direct energy  - epididymes  - electrically  Now knowing that ejaculation occurs when muscle contractions propel sperm from the epididymes and male orgasm and ejaculation are inhibited, choose the best answer.
epididymes

You are presented with the question "What can slowly dissolve carbon in sedimentary rock?" and the following answer choices:  - hydrocarbons  - acetic acid  - precipitation  - evaporation  - rivers and streams  - puddles  - ponds  - nitrogen  Now knowing that flowing water can slowly dissolve carbon in sedimentary rock and rivers and streams are bodies of fresh, flowing water, choose the best answer.

rivers and streams