"What's missing? It doesn't seem like there's anything missing, right?"
Fatty Chen had already sorted out everything that should be in the plastic bag from the perspective of eating and drinking.
"Ziploc bags, meat, bamboo sticks, cans and the drinks in the cans. Nothing else."
Judging from the plastic bags they were carrying when shopping and getting in the car, the plastic bags the Mosheng family was carrying were no different, and there was no shortage of either.
But some things are just invisible to you.
They obviously hold a lot of weight and are right in front of you, but you throw them into the trash can with your own hands, but afterwards you can't even remember that they ever existed.
"Just remember to eat and drink. In fact, there should be another very important thing in the plastic bag, and that is an ice pack."
Meng Fei patted Fatty Chen's fat face, which was in a daze because he was thinking hard.
"Generally tourists buy it at noon and have barbecue in the evening. If it is left for an afternoon, although it may not necessarily stink, the taste will change somewhat.
"The so-called original barbecue in this place is very particular about taste. So when meat is sold in supermarkets, it will definitely come with a lot of ice packs."
Meng Fei was very impressed by this. Because he was carrying the bag and it felt very heavy. The only thing that accounts for the weight is the drinks, which weigh several kilograms.
"In this case, after the vehicle fell into the water, the ice pack could not have disappeared for no reason. Why was it not found?"
Those ice packs are completely sealed in plastic wrap. Otherwise, once the ice melts, water will flow everywhere.
The ice pack is not entirely ice, but a gel-like substance that absorbs water easily. After being filled with water and frozen in a plastic bag, it can stay cold for a long time.
Even if the vehicle is soaked in water and the ice in the ice pack melts, the ice pack itself cannot disappear. But in fact, all the ice packs in the plastic bag are missing?
"But that's not surprising, right? If there are no more ice packs in the supermarket, we won't be able to give them to them. Besides, what does this have to do with the car falling into the lake?"
Chen Han still doesn't quite understand.
"Think about it, this car is called a sleep bus."
Meng Fei squeezed the can in his hand, hesitating whether to enjoy the refreshing feeling of the cold drunkenness passing through his throat.
Then he thought about the various changes in genes that alcohol promotes, leading to nasopharyngeal cancer, esophageal cancer, stomach cancer, and intestinal cancer along the digestive tract, and he gave up again.
"In addition to the comfortable lounge chairs, quiet and monotonous scenery, soft and comfortable road surfaces, and excellent sound insulation, there is actually another important factor.
“I saw that all the windows were closed, including the window next to the driver’s side. And the air conditioner was still circulating internally.
"Because this sleep bus is actually not very big, the internal space is small, and the ventilation is not very good, so the oxygen content will drop."
"oh!"
Fatty Chen patted his head.
"Are you saying that the people in this car were actually suffocated to death by the car?"
"No no no."
Meng Fei shook his head quickly.
"Even if the windows are closed, the car is ventilated. The air-conditioning internal circulation only reduces air exchange, not completely closed.
"The oxygen content in the car just drops slightly, making you feel sleepy. It is absolutely impossible to suffocate. Otherwise, it is not a sleep bus but a death bus!"
"Then how did the driver faint?"
"It would be dangerous if the oxygen content in the car could be quietly dropped and the carbon dioxide concentration kept rising."
Meng Fei imagined the scene at that time.
"Normal carbon dioxide concentration in the air is 0.03%. When it reaches 1%, people will have difficulty concentrating and become sleepy.
“Offices with poor ventilation may reach 2%, causing employees to feel sleepy, mentally fatigued and have reduced work efficiency.
“If the carbon dioxide concentration reaches 5%, people will lose consciousness and become confused.
"Although death is not guaranteed in a short period of time, on a long road with water on both sides, it is simply appropriate for the driver to drive the car into the lake.
"In this way, all the people were temporarily comatose due to suffocation caused by carbon dioxide, and then fell into the lake and drowned.
"Autopsy analysis showed that the cause of death was pulmonary edema caused by hypoxia. It is difficult to distinguish whether someone was comatose due to carbon dioxide before drowning.
"And carbon dioxide, of course, will disappear completely after being soaked in water, and no trace will be found in the test."
"Carbon dioxide? But where did the carbon dioxide come from? Did someone completely block the car's vents?"
“No need to block the vents.
"There is something that can continuously produce carbon dioxide. No one will suspect it if you bring it into the car, and no trace can be found afterward."
Meng Fei said pretending to be mysterious.
"I know what it is."
Fan Bu's eyes lit up.
"It's dry ice!"
"Um."
Meng Fei nodded.
“Usually supermarkets that buy and sell this kind of meat ingredients will have a lot of dry ice to keep the food cold during transportation.
“Edible dry ice is cylindrical or block-shaped and can be mixed with ingredients. The effect of maintaining low temperature is much better than ice packs.
"This is what the murderer did: when Mo Sheng and his family came to buy meat, they pretended that the ice pack was gone and replaced it with almost the same amount of dry ice.
"Dry ice does not need to be packaged because it will turn into gas and expand. If the package is closed, it will expand and explode.
"When it turns into carbon dioxide, it disappears. If soaked in water, it will turn into gas faster and leave no trace in the car afterwards. The only clue is that there is no trace in the big plastic bag containing the meat. ice bag."
Then Meng Fei started his "second calculation" process again.
“Visually, the sleep bus we have taken is about 6 meters long, 2 meters wide, and the internal space is 1.5 meters high, so the volume is 18 cubic meters.
"Under one standard atmospheric pressure, the volume of one kilogram of dry ice converted into carbon dioxide is approximately 0.5 cubic meters.
“The three of them bought about six kilograms of meat in total, and the amount of dry ice they added is probably about the same.
"If it is six kilograms of dry ice, converted into a volume of 3 cubic meters, in the sleep bus, the carbon dioxide concentration can increase to 3/18, about 16%, which is a complete suffocation.
"But the sublimation of dry ice into carbon dioxide is a slow process. And the car is not completely deventilated. It is like boiling a frog in warm water, and it is difficult for people in the car to notice.
“So about an hour after the bus departed, when the carbon dioxide concentration reached between 5% and 10%, both the passengers and the driver fell into coma and fell into the lake.
"If this is murder, it's absolutely brilliant!"
