The following data contain times to tumor relapse (in months) among 10 women with breast cancer.

The right censored observations are indicated by a +.

Genotype A : 12.5+, 3.3, 5.1+, 4.0, 5.0+.

Genotype B : 10.0, 2.5, 8.5+, 5.5+, 7.1+

Conduct a Gehan-Wilcoxon test (by hand) to examine whether time-to-relapse depends on genotype.