If a telescope originally costs $539.99 the tax rate is 10%. what is the total? pls someone explain how to solve these type of problems pl im not asking for a answer just explaining and possibly a example PLSS HELP ITS DUE IN 10 MINUTES

Find the amount in a continuously compounded account for the given condition. principal: $1000, annual interest rate: 4.8%, time: 2 yr

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.

In a survey of 1015 adults, a polling agency asked, "when you retire, do you think you will have enough money to live comfortably or not. of the 1015 surveyed, 534 stated that they were worried about having enough money to live comfortably in retirement. construct a 90% confidence interval for the proportion of adults who are worried about having enough money to live comfortably in retirement.