The sums of any series can be found under F2 C , just enter the series. Thats for questions 1 and 2
Now, since the series in 1) is a converging geometric series you could also use the geometric series test under F2 3 .
For 3) use the integral test under F2 4 : enter as 1/(n*(ln(n)^3))
For 4) use F1 3
oo infinity symbol is at Diamant+catalog