Resistor Calculator exercise

R = Vs-Vled/Iled

1-  150 = 5-2/20 mA

2-   95 = 5-3.1/20 mA

3-  85 = 5-3.3/20 mA

4-  160 = 5-1.8/20mA

5- 100  = 5-3/20mA