The following table gives the frequency distribution of the number of telephones owned by a sample of 50 households selected from a city.

Number of Telephones Owned	Frequency
0	3
1	21
2	15
3	5
4	6

a. The relative frequency of the second class, rounded to two decimal places, is: _____

b. The number of households which own more than one telephone is: _____

c. The percentage of households which own three or more telephones is: _____

d. The number of households which own one or two telephones is: _____

e. The percentage of households which do not own a telephone is: _____

f. The number of classes for this frequency distribution table is: _____