Problem: What is the missing first step of the following process:  -  Bees will begin to chew max until it becomes softened - The chewed up wax will be stored inside of a honeycomb - Worker bees continue chewing and softening wax from within - The chewed up wax is steadily added, making the hive bigger and bigger - The bees will house nectar, honey and pollen within the honeycomb's cells -

A: Bees first secure the perfect spot, such as hollow areas of trees


Problem: What is the missing first step of the following process:  -  Rain picks up carbon dioxide as it falls to earth - The rain falls on the soil over the limestone - The carbon dioxide in the rain washes through the soil - The carbon dioxide turns into acid - The acid in the rain gets to the limestone below the soil - The acid dissolves the limestone - Acid continues to erode the limestone with more rain over time - The eroded limestone sometimes forms caves.

A: Limestone is located under the soil


Problem: What is the missing first step of the following process:  -  Blood is carried to the kidneys through the renal arteries - The kidneys contain filters inside - The filters capture the waste products - The waste is combined with water to make urine - The urine leaves the kidney and is collected in the bladder - The cleaned blood is returned to the body.

A: Waste products are deposited in the blood


Problem: What is the missing first step of the following process:  -  Water is in the air - The water forms tiny ice crystals - The ice crystals collide with each other - The ice crystals stick to each other - The ice crystals get bigger as more of them stick together - The ice crystals get too heavy to be in the air - The ice crystals become snowflakes - The snow flakes fall to the ground as snow.

A: