In order to determine whether or not a particular medication was effective in curing the common cold, one group of patients was given the medication, while another group received sugar pills. The results of the study are shown below.

Patients

Cured

Patients

Not Cured

Received medication80

10

Received sugar pills20

50

We are interested in determining whether or not the medication was effective in curing the common cold.

The hypothesis is to be tested at the 10% level of significance. The critical value from the table equals

a.5.99

b.3.841

c.7.81

d.2.706