Question: If I use `(body).height();` to calculate a windows height, is there a way to calculate the height -100px. 

Is there a way to do this as part of the `(body).height();` query rather than calculating it later on ?

Answer: 
```
($(body).height() - 100)

```

Just... subtract?
The fastest way would be :

```
var H = $(body).height() - 100 + 'px';
console.log(H);

```