Problem: What is the missing first step of the following process: - Babies become infants - Infants become children - Children learn skills - Children become teenagers - Teenagers undergo puberty - Teenagers become adults - Adults have children - Adults become elderly - Elderly humans die.

A: Humans are born as babies

Problem: What is the missing first step of the following process: - Chemical compounds rise into the air - Chemical compounds mix with elements in clouds - The affected rain falls to the earth - The affected rain can harm natural and man-made objects because of its acidic content.

A: Human industry produces chemical compounds

Problem: What is the missing first step of the following process: - A selection of grapes are gathered - The grapes are washed - The stems are removed from the grapes - The grapes are crushed and added to a fermation container - Yeast is added to the container - The yeast eats the sugar in the yeast, releasing alcohol -

A: Grapes are grown

Problem: What is the missing first step of the following process: - The brain tells blood vessels to dilate - The sweat glands become active - Moisture is released from the pores - The moisture evaporates - The evaporation causes cooling.

A:
Body temperature rises