PLEASE ANSWER TODAY ASAP WILL GIVE BRAINLIEST FOR FIRST CORRECT ANSWER. Angle a and angle b are complementary angles. The measure of ∠a is 42°.

Which equation represents this situation with x representing the measure of ∠b?

42−x=90

90+x=42

42+x=90

90+42=x

Amass weighing 16 pounds stretches a spring 8/3 feet. the mass is initially released from rest from a point 2 feet below the equilibrium position, and the subsequent motion takes place in a medium that offers a damping force that is numerically equal to 1/2 the instantaneous velocity. find the equation of motion if the mass is driven by an external force equal to f(t)=cos(2t).