Why are some volcanoes explosive and others not?

It depends on the composition of each volcano's magma. Some volcanoes erupted with loud explosion while the other only spurt out the lava peacefully. There's also some volcanoes which not erupting but it was considered as an active volcano and that's all depends on the composition of the magma. (hope it helpful)

May consider a group  g=({0,1},+)g=({0,1},+)where  ++  will work as the xor operator like we work in boolean algebra. note here, that ‘00’ and ‘11’ are not the usual 0 and 1 that we work with everyday. the elements are  called  ‘00’ and ‘11’ and  may not mean  zero (nothing) and one (single). ‘00’ is the identity for the given binary operator +, meaning that any element operated with ‘00’ gets us that element itself.  for a set  ss  in  g′g′  having more elements than just  {0,1}{0,1}  the values for  a+b∈sa+b∈s, such that  a∈s,b∈sa∈s,b∈s, have to be first defined, only then can you determine the value of  1+11+1. the answer could possibly have been  22  if oanswer is25,000

Answerencourage alternative timber sources,increase public awareness of the forests,increase research into forestry,involve local communities in forest projectsalso one of the main initiatives of the 1977 act was to introduce a new approach to forest management known as selective management system, this is recognised as one of the most sustainable approaches to tropical forestry management in the world