Let \( W = f(u) \) be the temperature, in \( ^\circ C \), of a chemical reaction \( u \) hours after the reaction starts. The temperature varies sinusoidally and oscillates between a low of 30 \( ^\circ C \) and a high temperature of 110 \( ^\circ C \). The temperature is at its highest point when \( u = 0 \) and completes a full cycle over a 4-hour period.a. Find the amplitude, midline and period of \( f(u) \).- The amplitude of \( f(u) \) is \(\boxed{40}\) \( ^\circ C \).- The midline of \( f(u) \) is \(\boxed{70}\) \( ^\circ C \). (Note: you should give an equation for the midline as your answer.)- The period of \( f(u) \) is \(\boxed{4}\) hours.b. Find a formula for the sinusoidal function \( W = f(u) \).\[ f(u) = \boxed{70 + 40 \cos\left(\frac{\pi}{2}u\right)} \]

Given that Let W = f(u) be the temperature, in °C, of a chemical reaction u hours after the reaction starts. The temperature varies sinusoidally and oscillates between a low of 30 °C and a high temperature of 110°C. The temperature is at its highest point when u = 0 and completes a full cycle over a 4-hour period.The standard sine function and the standard cosine function is Amplitude Midline Phase shift , T= time periodFrom the given information The maximum value of the function is The minimum value of the function is The amplitude of the function The graph completes its one cycle from Therefore The period of the function is NowGiven that the temperature is at its highest point when u = 0Then we use value of Here the maximum value of cosine function also exists at then no phase shift for cosine function so Now the equation of cosine function Now we know Conclusion Hence(a) The amplitude of f(u) is The midline of f(u) is The period of f(u) is hours (b) The sinusodial formula