Mark purchases a Nintendo switch for $300 sales tax is 8% on all purchases how much sales tax does Mark pay

Can someone me my sister? she is in third grade. 50 points and brainlist! ones that are not answered. plz and thx!

An ulcer medication has 300 milligrams in 2 tablets. how many milligrams are in 3 tablets?

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.