With sn denoting the sum of the first n terms of an arithmetic sequence, we are given that s1=9 and s2=20
a) find the 2nd term
b) calculate the common difference of the sequence
c) find the 4th term

The academic affairs council is the highest expert body processing academic affairs, as stipulated by the university statutes. specialist aaro häkkinen (educational policy) took part in the council’s meeting. the agenda of the meeting included bachelors’ feedback, the timing of pedagogical studies, the grant system for tuition fees, the standardisation of administrative practices for internships and the situation of foreign-language and multilingual master’s programmes.