The Big Bang, Time & Space

These are concepts that boggle my mind. Scientists study these areas in terms of physics using high-level calculus. I managed a “D” in college in physics (I think I forgot the location of the classroom). I bought a copy of Calculus for Dummies. I also managed a “D” in college trigonometry (It could have been the same classroom). After 40 pages in my calculus book, I googled for a copy of Calculus for “Dummer” than Dummies. I couldn’t find it.

What existed before the Big Bang? How is it possible for a singularity to be dense enough to contain all the matter in our Universe (not just the matter we know about, but also “dark” matter)? What caused it to bang? Where was the singularity before it banged? How is it possible for the explosion to continue accelerating after over 13 billion years? Did time exist in another realm prior to the big bang? How can the size of our observable universe be larger, in terms of light years, than the amount of time it has existed? Do we really know what we don’t know?