What do the parts of expression 48s represent?

Given a(-12,5) and b(12,29) find the point that divides the line segment ab three-eighths of the way from a to b

Let w=23 . what is the value of w + 45 ?

Which is the standard form for this number? (4 x 1 100 ) + (8 x 1 1,000 ) + ( 3 x 1 100,000 ) ? a) 0.004803 b) 0.04803 c) 0.0483 d) 0.483