In each of the following studies identify the explanatory and response variables and whether or not the researchers could conclude cause and effect. Justify your answers using complete sentences.

(a) In a random sample of countries, it was found that countries where more citizens have internet access also have higher life expectancies.

(b) Students were randomly assigned to two groups. One received their exam on blue paper and the other used green paper. The group using blue paper scored higher than the group using green paper.