When we talk about doing multiple things with a computer be at we are doing things on the internet or just doing things locally then the first thing that we would like with a computer is how fast our things can be done.
Yet, it is not the RAM that will determine that enable one to do multiple things fast but how well the computer is being maintan. Of cause a higher RAM help a lot but basically the RAM and the CPU goes hand and hand.
The most important thing that should be done is avoid to clogging up a computer with unnecessary software or keeps unnecessary files such as photos and videos that takes a lot of space that further slowing down your computer. Therefore, 1Gb of RAM is sufficient to run multiple tasks as long as the computer is well maintained.