Can someone help me with this question? I'm bad at solving this problem. Outside temperature over a day can be modelled as a sinusoidal function. Suppose you know the high temperature for the day is 84 degrees and the low temperature of 56 degrees occurs at 4 AM. Assuming t is the number of hours since midnight, find an equation for the temperature, D, in terms of t. Please I want to know the solution and the answer. ASAP

According to a study conducted in 2015, 18% of shoppers said that they prefer to buy generic instead of name-brand products. suppose that in a recent sample of 1500 shoppers, 315 stated that they prefer to buy generic instead of name-brand products. at a 5% significance level, can you conclude that the proportion of all shoppers who currently prefer to buy generic instead of name-brand products is higher than .18? use both the p-value and the critical-value approaches.