If a=3 what is the value of 2a2

Write the sine and cosine values of a, b, respectively, in the figure for (1) and (2) + explanation.

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

The product of sin 30 degrees and sin 60 degrees is same as the product of