6. The length of time per week that students in an online math class devote to learning the material and interacting with the course is normally distributed, with a mean of 18.6 hours and a standard deviation of 2.1 hours. a. Build a number line with the mean in the middle and add/subtract the standard deviation 3 times. Label each \% above the number line using the \( 68-95-99.7 \) Rule.

An anonymous survey of college students was taken to determine behaviors regarding alcohol, cigarettes, and illegal drugs. The results were as follows: 852 drank alcohol regularly, 640 smoked cigarettes, 185 used illegal drugs, 395 drank alcohol regularly and smoked cigarettes, 108 drank alcohol regularly and used illegal drugs, 113 smoked cigarettes and used illegal drugs, 86 engaged in all three behaviors, and 103 engaged in none of these behaviors. a) How many students were surveyed? 1250 Of those surveyed, b) How many drank alcohol or smoked cigarettes? 1097 c) How many used illegal drugs only? 50 d) How many drank alcohol and used illegal drugs, but did not smoke cigarettes? 22 e) How many drank alcohol or smoked cigarettes, but did not use illegal drugs?

Ewren \( f(x)=-x^{2}+2 x+3 \) \( g(x)=1-2^{x} \) 9.1. sketh the graphs on Same set of axis 92. Determune the average gradent of \( f \) between \( x=-3 \) and \( x=0 \) 9.3. for which values of \( x \) \( f(x) . g(x) \geq 0 \)

Solve the system by the substitution method. \[ \begin{aligned} x+2 y=10 \\ y=4 x-13\end{aligned} \] Select the correct choice below and, if necessary, fill in the answer box to complete your A. The solution set is \( \} \). (Type an ordered pair.) B. There are infinitely many solutions. C. There is no solution.

3. \( 2 x^{2}-28=0 \)

Find the derivative of the following function. \[ f(x)=5 x^{4} \ln x \]