Find the missing side lengths answered in the simplest radical form with the denominator rationalized ​

Alicia puts $400 in a bank account. each year the account earns 5% simple interest. how much money will be in her bank account in six months?

Which of the expressions (on the photo document i inserted) together represent all solutions to the following equation? 8cos(12x)+4=-4 *the answer should be in degrees.* > i would like for someone to explain the process to find the solutions for this.

The function show two sisters' savings account and the rate at which they plan to deposit money