Problem: What is the missing first step of the following process: - The can is taken to a recycling center - Melted down along with other cans - The melted metal is turned into bars - Becomes material for other products.

A: A can is thrown away into a recycling bin

Problem: What is the missing first step of the following process: - Under the right conditions it can develop further and start to spin around a low-pressure center - If it develops it's classified as a 'tropical cyclone' or 'tropical depression' - If the system strengthens and wind speeds rise past 39 mph, the system is dubbed a 'tropical storm' - If the pressure in the center drops even further and the winds really pick up and forms a clearly defined 'eye' it's a hurricane -

A: A hurricane usually starts as an organized thunderstorm activity that stretches at least 100 miles across and maintains its identity for more than 24 hours

Problem: What is the missing first step of the following process: - The blood travels into the neophrons - Waste is expelled via the neophrons - The waste goes to the bladder in the form of urine - The clean blood exits the kidneys.

A: Blood enters the kidney

Problem: What is the missing first step of the following process: - Your thermostat sends a signal to your heating system to provide heat for your home - When your oil burner is engaged, heating oil travels from the tank to the burner by way of a pump - Here the oil becomes a fine mist mixed with air - The fuel/air mixture is then injected into the burner where it is ignited in the combustion chamber - The warm air is disbursed through vents, hot water through baseboards, or by steam radiators -

A:
Your thermostat senses that the room temperature has fallen below your thermostat setting