The number of people in a car that crosses a certain bridge is a random variable X having a mean value of 2.7 and variance of 1.2. The toll on the bridge is $3 per car plus $.50 (50 cents) per person in the car.

1. An expression for the amount of money that is collected from a car that crosses the bridge is:
   
   .5-+3X
   

   3+.50X
   

   3.50X
   

   3.50
   
   
   
   
2. Given your answer to the previous question, and using the first set of rules for means and variances, what is the mean and standard deviation of the amount of money that is collected from a car that crosses the bridge?
   
   • mean = $4.35, standard deviation = $$\displaystyle \sqrt{{{3.60}}}$ 
   • mean = $1.35, standard deviation = $$\displaystyle \sqrt{{{.30}}}$ 
   • mean = $9.45, standard deviation = $$\displaystyle \sqrt{{{.30}}}$ 
   • mean = $4.35, standard deviation = $$\displaystyle \sqrt{{{.30}}}$ 
   • mean = $4.35, standard deviation = $$\displaystyle \sqrt{{{.60}}}$