over 40% of Belorussian territory is covered in trees, If Belorussian is 80,153 what amount of land is not forest

In an experiment you are to flip a two sided coin 100 times and record 55 heads up and 45 tails up determine the theoretical and experimental probability of getting a heads up in the experiment.

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

0if x and y vary inversely and y=6 as x=7, what is the constant of variation?