can someone help plz.

01 Remaining Time: 04:49:42 Two fixed sides of a triangle are 10 m and 21 m in length. The angle between them is changing and the area of the triangle is increasing at a rate of 3 m 2/s. Find the rate at which the angle between the fixed sides is increasing when the area is 210- 3 and the angle between the fixed sides is an acute angle. Note: Write only the numerical value of the rate, the units are already written. Write the exact answer not the decimal approximation (for example write not 0.5). Answer: The angle is increasing at a rate of radi's