下列加线实词全都正确的一项是（ ）

At lessthan $100 this smart and digital camera is good _______ for money.

The government will begin a series of_____ to help thepublic fully understand the new educational system

How long has David’s grandfather ______ -About two months.

Have you_______ the film “Black coal, Thin ice” -Of course. It won the Best Film Award in the 65th Berlin Film Festival. I don’t mind _______ it again if you invite me to.