Help me with this?

So today I got a Seasonal Job at Amazon. I work 4 days a week making $10.75 and Also $15.50 on Saturday and Sunday. Right now I don't have a vehicle, ill be saving to get one. The Drive is 25 miles down and 25 miles back home. What would the reasonable amount of money to give to my mom in a week for taking me to and from work til I can get a Vehicle??