Cot^4+ cot^2= cosec^4 - cosec^2
please prove the identitiy ​

Onnie is considering doing some long term investing with money that she inherited. she would like to have $50,000 at the end of 30 years. approximately how much money would lonnie need to put into an account earning 6% interest compounded annually in order to meet her goal?

Tobias gold sells computers at the office center he's guaranteed a minimum salary of $1,959 per month plus 6.3% commission on total sales how much in total sales is he

The perimeter of the rectangle is 120 feet. if the length of the rectangle is ten feet more than the width ,what are the dimensions (length and width) of the rectangle?