List factors of 20 i am smart but i have so much homwork pleaz

What is the simplified form of (3.25x10^3)(7.8x10^6) written in scientific notation?

Ur environment is very sensitive to the amount of ozone in the upper atmosphere. the level of ozone normally found is 4.04.0 parts/million (ppm). a researcher believes that the current ozone level is not at a normal level. the mean of 2525 samples is 4.44.4 ppm with a standard deviation of 0.80.8. assume the population is normally distributed. a level of significance of 0.020.02 will be used. make the decision to reject or fail to reject the null hypothesis. answer tables

Arational number that is equivalent to -20/4?