7. For the decomposition of (CH3)20 (species A) at 777 K, the time required for [A], to fall to 0.69[A], as a function of [A], is: 103 [A], (mol dm-3) to.69 (s) 8.13 6.44 3.10 1.88 590 665 900 1140 (a) Determine the order of the reaction graphically. (Give the final answer to one decimal place.) d[A] (b) Determine the value of ka (include appropriate units) in = -kA[A]*. Show detailed dt workings. (Give the final answer to three significant figures in scientific notation.)