Stephanie is 12 years old and often assists neighbors on weekends by babysitting their children. Calculate the 2018 standard deduction Stephanie will claim under the following independent circumstances (assume that Stephanie’s parents will claim her as a dependent). 

a. Stephanie reported $850 of earnings from her babysitting.
b. Stephanie reported $1,500 of earnings from her babysitting.
c. Stephanie reported $18,000 of earnings from her babysitting.