Q: Restoring nitrogen to the soil is one reason for what agricultural practice? Choices: - irrigation - plowing - sowing - crop rotation A:
crop rotation

Q: Ultimately, most life forms get their energy from this? Choices: - heat - earth - food - sun A:
sun

Q: Ejaculation occurs when muscle contractions propel sperm from where? Choices: - cervix - penis - urinary track - epididymes A:
epididymes