Help me w this questions, i’ll give extra points!

What kinds of numbers make up the set of numbers called the real numbers? give examples when you explain a number type. there are a limited set of types of numbers, but an unlimited number of examples of these numbers.

The brain volumes (cm cubed) of 50 brains vary from a low of 904 cm cubed to a high of 1488 cm cubed. use the range rule of thumb to estimate the standard deviation s and compare the result to the exact standard deviation of 175.5 cm cubed, assuming the estimate is accurate if it is within 15 cm cubed

Y=(x+3)(x-4)(x+1)^2 sulutions? multiplicity?