4. A force of 5 pounds acts in the direction of 5" to the horizontal. The force moves an object along a straight line from the point (5, 4) to the point (18, 13), with distance measured in feet. Find the work done by the force. Round the answer to one decimal place, If necessary. O A. 109.6 ft-lb O B. 79.1 fl-b O C. 15.8 fl-b O D. 78 8 ft-1b 9. Find a. If necessary, round your answer to the nearest hundredth. 36 61 O A. 9.66 O B. 7:28 O C. 16.68 O D. 6.22 10. Find the product of the following complex numbers. Leave answer in polar form. 21 = 5(cos 20" + / sin 20") z2 = 4(cos 10' + / sin 10") O A. 9(- cos 200' - / sin 200") O B. 20(cos 30* + / sin 30") O C. 9(cos 30* + / sin 30*) O D. 20(cos 200* + / sin 200")11. Use the given vectors below to find the specified scalar: # = 9/-6/, v=-8/-9/, w= -10/ + 5/; Find u(v + w). O A. -18 O B. -138 O C. -120 O D. 72 13. Convert the following polar equation to a rectangular equation. Then determine the graph's slope and y-intercept. rsin e -* =5 O A. y- -x-5v2: slope -1; y-intercept: -512 O B. y- x +5:2: slope: 1; y-intercept: 51/2 O C. y- -x +5v2: slopec -1; y-intorcopt: 5:/2 O D. y- x-5 2: slope: 1; y-intercept: - 5:/2 16. A child throws a ball with a speed of 5 feet per second at an angle of 54" with the horizontal. Express the vector described In terms of / and j. If exact values aren't possible, round components to 3 decimals. O A. 4.0457 + 2.939j O B. 2.939/+ 4.045/ O C. 4.0451-2.939/ O D. -2.939/ + 4.045/ 20. Find the following specified vector: u = 12/- 3j, v= -3/ + 8/: Find u + v O A. 8/ + 5/ O B. -15/ + 5j O C. 15/ + Bj O D. 97 + 5j