Katie sends a letter to 6 friends. Those 6 friends each send the letter to 6 more friends, who all send the letter to George. How many letters does George get? PLZ HELP ME they got too many people in the problem

Which number completes the inequality? 2/3 < _ < 7/9

The area (a) of a circle with a radius of r is given by the formula and its diameter (d) is given by d=2r. arrange the equations in the correct sequence to rewrite the formula for diameter in terms of the area of the circle.

Asinusoidal function whose frequency is 1/6pi