How to write 3,801,440 in expanded form

The diameter of a circular chip is doubled to use in a new board game. the area of the new chip will be

A. 90 degrees b. 45 degrees c. 30 degrees d. 120 degrees

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.