The complete set of common factors of 6 and 12 is:
a.{6, 12}
b. {1, 6, 12}
c. {1, 2, 3}
d. {1, 2, 3, 6}
e. {24, 48}

b.) 160 miles on a 5 gallons car

step-by-step explanation:

240/10=24 miles/gallon

160/5=32 miles/gallon

30/1=30 miles/gallon

168/6= 28 miles/gallon

32 miles/gallon is the most amount, so this is the best.