`[1] 1000`

`[1] 1035`

`[1] 2035`

`[1] 35`

`[1] 742775`

Exercise

The following code estimates the total net primary productivity (NPP) per day for two sites. It does this by multiplying the grams of carbon produced in a single square meter per day by the total area of the site. It then prints the daily NPP for each site.

```
site1_g_carbon_m2_day <- 5
site2_g_carbon_m2_day <- 2.3
site1_area_m2 <- 200
site2_area_m2 <- 450
site1_npp_day <- site1_g_carbon_m2_day * site1_area_m2
site2_npp_day <- site2_g_carbon_m2_day * site2_area_m2
site1_npp_day
site2_npp_day
```

Copy this code into your assignment and then add additional lines of code to do the following steps and print them out after the daily NPP values (the ones currently printed by the code):

- The sum of the total daily NPP for the two sites.
- The difference between the daily NPP for the two sites. We only want an absolute difference, so use abs() function to make sure the number is positive.
- The total NPP over a year for the two sites combined (the sum of the total daily NPP values from part (1) multiplied by 365).

Output solution

`[1] 1000`

`[1] 1035`

`[1] 2035`

`[1] 35`

`[1] 742775`