Many people think it is very exciting and admirable(令人羡慕的) to be an actor. The actors often wear the most beautiful and fashionable clothes and they can make a lot of money. Many people like them and they have so many fans. But in fact, the job of an actor can be very tiring and hard. To make good movies, for example, action movies, the actors need to go to some remote(偏远的) places. There they don't have good places to stay or nice food to eat. They often have to get up early and go to bed very late. When they are too busy, they don’t have time to sleep or relax. It's very hard.

求下面三角形的面积．

面积是____ $d{m}^2$