Compute all parts of given problem:
Problem: Luigi wishes to suspend a lantern of mass m between his store and a telephone pole. The cable attached to his store makes an angle (theta) to the wall. The cable to the telephone pole is horizontal.
Part A: What is the tension in the cable of angle (theta)?
Part B: What is the tension in the horizontal cable?
Part C: Calculate the two tensions for a 12 kg lantern with (theta)=40degrees?
Please show all work and steps to determine the tension in the horizontal cable.