Defines a one-to-many dependency relationship between objects. When the state of an object changes, all objects that depend on it are notified and automatically updated.
As online organizations have broken the time and geographical restrictions, they have saved the time and transportation costs that parents and children have to pay. Secondly, it has the natural advantage of directly facing the national market and allocating the national teacher resources, breaking the regional restrictions on obtaining customers and employing teachers. In addition, in the process of scale-up, online organizations do not need to invest in the training of stores and store managers, so the upfront investment is relatively low.
4. Large investment, The density is too high when the water supply is not available, Misgurnus anguillicaudatus invested about 500 kg, Monopterus albus invested about 100 kg, and snails invested about 3,000 kg. These items were basically not sold back at all. The workers hired two, 6,000 a month. The reason was that they were too optimistic about the prospect, the workers did not pay attention, and they basically had to worry about themselves. Therefore, the breeding should be done slowly by their own family as far as possible, and people should be hired when the scale went up.
Weightlifting is a training event that constantly challenges self-limit and strong load. It is not easy for male athletes, especially for relatively delicate female athletes. It is amazing to see with one's own eyes the amount of training they have in one day. A girl who weighs about 100kg and is 15 or 16 years old can easily lift a barbell weighing more than 180 kg. Push-ups that practice strength can reach 20 or 30 at a time. The 15 kg iron plate used for practice can be lifted back and forth 50 or 60 times. "You don't see these girls are thin, they can lift more than twice their own weight, in preparation for the provincial games, these girls have to lift a total of 3 tons of weight every day, that is, 6000 kg! Even in normal training, they have to lift an average of about 2 tons a day." Liu Eryong told reporters, "Take a 60 kg female player as an example. She lifts the 100 kg barbell eight times a day, plus the process of slowly increasing from 70 kg and 80 kg to 100 kg, the clean and jerk alone can lift one ton. This is the first event, and the back squat exercise will be done later. The barbell used for the exercise is about 140kg, and it also requires eight groups, which is more than one ton. Plus some warm-up actions such as lifting empty barbells and discus, it is no problem to lift two or three tons after three hours in a class. " For ordinary adolescent girls, being able to carry a large bucket of water weighing 30 kg is already a female man. Like female lifters, lifting two or three tons a day and taking more than 20 training sessions a month is nearly 60 tons, which is a real girl of the universe!