Номер 4 помогите плз (только решение и ответ)

1. the rules must not be broken 2. the new school is being built at the moment. 3. The Mayor will open the school building will be opened by the Mayor this Tuesday. 4. the task have been done without any problems. 5. his advice should be followed by you

25-29=5 шт -разница в количестве изделий10 :5= 2 м - на 1изделие