What is lightning? A. The release of sound between a cloud and the ground.

B. The flow of electricity between a cloud and the ground.

C. The flow of light between a cloud and the ground.

D. The rapid flow of air between a cloud and the ground.

B. The flow of electricity between a cloud and the ground.

significant amounts of nitrogen oxides, carbon monoxide, and other pollution

explanation:

passenger vehicles are a major pollution contributor, producing significant amounts of nitrogen oxides, carbon monoxide, and other pollution. in 2013, transportation contributed more than half of the carbon monoxide and nitrogen oxides, and almost a quarter of the hydrocarbons emitted into our air.

the menstrual cycle – higher tier. negative feedback mechanisms affect the production of hormones in the menstrual cycle. oestrogen also stimulates the release of lh (luteinising hormone) from the pituitary gland, which in turn controls the production of progesterone.