I'm having difficulties on these word problems can anyone please help.

1. The displacement of a spring vibrating in damped harmonic motion is given by the following equation. Find the times when the spring is at its equilibrium position,y= 0.

2. As the moon revolves around the earth, the side that faces the earth is usually just partially illuminated by the sun. The phases of the moon describe how much of the surface appears to be in sunlight. An astronomical measure of phase is given by the fractionFof the lunar disc that is lit. When the angle between the sun, earth, and moon isθ(0 ≤θ< 360°), then the fractionFis given by the formula below. Determine the anglesθthat correspond to the following phases.

3. Consider the equation.

(a) Use an addition or subtraction formula to simplify the equation.

(b) Find all solutions in the interval [0, 2π). (