Anybody need any 4rth 5th 3rd grade math help or reading or writing im here!!

Me n o w. i need t h i s. 10 points

The customer price index(cpi), which measures the cost of a typical package of customer goods,was 208.8 in 2011 and 244.1 in 2016.let x=11 corresponding to the year 2011 an estimate to cpi into 2013 and 2014. assume that the data can be modeled by a straight line and the trend to continue idenfinitely.use data points to find such a line and then estimate the requested quantities

At noon a tank contained 10cm water. after several hours it contained 7cm of water. what is the percent decrease of water in the tank?