How much interest is earned on a principal of $4.62 invested at an interest rate of 7% for two years

Which shows the correct solution of the equation 1/2a+2/3b=50, when b=30?

The pyramid below was dissected by a horizontal plane which shape describes the pyramid horizontal cross section

In 2009, there were 1570 bears in a wildlife refuge. in 2010, the population had increased to approximately 1884 bears. if this trend continues and the bear population is increasing exponentially, how many bears will there be in 2018?