c) Work out
2.9 x 105 * 7.2 x 102
(Over) 5 x 10-8

Answer: 417,600,000,000,000
Step-by-step explanation: 2.9(10)^5(7.2)(10^2)/5(10^-8)
(2.9)(100,000)(7.2)(10^2)/5(10^-8)
(290,000)(7.2)(10^2)/5(10^-8)
2,088,000(10^2)/5(10^-8)
(2,088,000)(100)/5(10^-8)
208,800,000/5(10^-8)
208,800,000/5(1/100,000,000)
208,800,000/1/20,000,000
417,600,000,000,000