The equation /= -1 12.3 In 0.5 is a mathematical model for the W 1.008 relationship between the weight W (in grams) of an individual leaf of a wheat plant and the number of days t since the leaf unfolded from the stalk of the plant. The weight of a certain leaf is 13.1 grams. According to this model, how many days ago did the leaf unfold? (Round to the nearest tenth of a day.) 0.4 days 1.5 days 1.4 days 0.8 days 0.5 days