Two Sample t-test
data:  psychologie and chemie
t = 4.655, df = 28, p-value = 3.561e-05
alternative hypothesis: true difference in means is greater than 0
95 percent confidence interval:
 1.716205      Inf
sample estimates:
mean of x mean of y 
 17.11430  14.40972 
 Two Sample t-test
data:  psychologie and physik
t = 3.3692, df = 28, p-value = 0.001106
alternative hypothesis: true difference in means is greater than 0
95 percent confidence interval:
 1.069361      Inf
sample estimates:
mean of x mean of y 
 17.11430  14.95436