Solve the all parts of given question:
Question: A heating element is made by maintaining a potential difference of 80.0 V across the length of a Nichrome wire that has a 2.94 × 10-6 m2 cross section. Nichrome has a resistivity of 5.00 × 10-6 Ω•m.
Part A: If the element dissipates 7870 W, what is its length?
Part B: If 103 V is used to obtain the same dissipation rate, what should the length be?
Please show all work and steps I am really trying to learn this for my exam.