1、

(1) If a bag filled with 25 kilometers is regarded as a cuboid, its length, width and height are about (0.5) m, (0.4) m and (0. 1) m respectively, and its volume is about (0.02)m? .

② A warehouse is 8m long, 5m wide and 3m high, which is equivalent to the size of a classroom. What volume can it hold (120)m? .

(3) One such warehouse can hold about (6,000) bags of rice, which is equivalent to (150,000) kilograms of rice.

④ About (167) warehouses are needed to store 2.5 million kilograms of rice.

⑤ If one truck can transport 10 tons of rice at a time, it will take (250) trucks to transport 2.5 million kilograms of rice to the disaster area at a time.

2、

I asked my parents that my family uses about 3 tons of water a month. I estimate that one person needs about (33) kilograms of water every day, and 5 million people need about (6.5438+0.65 million) tons of water every day.

I checked the information and found that in order to maintain life, everyone needs about 2.5 liters of water every day, and 5 million people need about (12500000) liters of water every day.