Can someone please explain it to me ASAP??!!! This is physical application

Points: 0 of 1 The figure to the right shows the shape and dimensions of a small dam. Assuming the water level is at the top of the dam, find the total force on the face of the dam. Use 1000 kg / my -60 m for the density of water and 9.8 m / s for the acceleration due to gravity. 45 m +30 m - Find the width function w(y) for each value of y on the face of the dam. Place the origin at the center of the base of the dam, with the y-axis going in the vertical direction and the x-axis going in the horizontal direction. Choose the correct answer below. 3 OA. W(y)= 7(y+ 45) O B. W(y) = 7(y+45) O c. w(y) = 90y O D. w(y) = 2025y