Answer:
Russell needs to weigh out 0.035 grams of powder.
Explanation:
Suppose, the weight of the powder in grams

Given that, the weight of the powder is 35 milligrams.
The ratio of grams to milligrams is

According to the given ratio, we will get......
![(x)/(35)=(1)/(1000)\\ \\ 1000x=35\ \ [by\ cross\ multiplication]\\ \\ x=(35)/(1000)\\ \\ x=0.035](https://img.qammunity.org/2018/formulas/mathematics/high-school/ekpaep4scxerc27v5c52q0gr3xgq2ri3vm.png)
So, Russell needs to weigh out 0.035 grams of powder.