Who knows some websites that i can get 6th grade math questions from ?

Given the following sampling distribution of one mean with a sample size 49, from a normally distributed population, find the population standard deviation, o.79828588912497

What are the first 4 terms in the multiplication pattern given by the formula 2×4n

Aswimming pool had 2.5 million liters of water in it. some water evaporated, and then the pool only had 22 million liters of water in it. what percent of the water evaporated?