Tags are very common in spoken English, and have many functions. One of the common functions is to start a conversation or help keep it going. The two basic rules about tag questions are:1  If the statement is negative, the tag must be positive.ags are very common in spoken English, and have many functions. One of the common functions is to start a conversation or help keep it going. The two basic rules about tag questions are:
The average cost for a community to fluoridate its water is estimated to range from approximately $0.50 a year per person in large communities to approximately $3.00 a year per person in small communities. For most cities, every $1 invested in water fluoridation saves $38 in dental treatment costs.55 âFor most cities, every $1 invested in water fluoridation saves $38 in dental treatment costs.â It can be calculated from these data that the average lifetime cost per person to fluoridate a water system is less than the cost of one dental filling.
How much does it cost to install a water softener? Angie's List members who had a water softener installed in 2013 reported paying an average of about $1,690, with a general range near $1,875 to $2,060, not counting discounts many service providers offer to members. Water softeners themselves usually cost about $1,000 to $2,000. Even though this may seem like a lot of money, a water softenerâs lifespan is about 15 years.