You don't need to answer problem 1, just use problem 1 to answer problem 4. Please show complete solutions, thank you.

Problem 1 [Related Rates]: (15 points) Monmon, 165 centimeters in height, is approaching the UST Main Building around 50 meters high at a constant rate of 1 meter per second along Lovers' Lane, while staring at the beauty of the said building . Find how fast the subtended angle (in degrees per second) of the UST Main Building is changing with respect to time when Monmon is 150 meters away from the Main Building. Calculators will be allowed for this specific problem. Express your answers accurate to four decimal places. Problem 4 [Rectilinear Motion]: (20 points) Give the time interval during which the particle in Problem 1 is speeding up to the right