Question 6: note that the sun can never be at the zenith for lincoln (lat = 41°n)? how far

would you need to move on the earth to find a latitude where the sun can be at the

zenith?

Hey this is your answer

You need to figure out at which x-value does the graph has a tangent line slope of -1.remember, the derivative is the slope of the tangent line. so find the derivative function and set it to equal -1 to find the x-value that will have a tangent line slope of 0.differentiate with the chain rule.    set the derivative to equal -1 and solve for x.      take log base 10 of both sides. also recall that  .    so the x-coord of the point of tangency is .the y-coordinate of this point of tangency can be calculated using the original function:     using point-slope form, the equation of the tangent line is      the x-intercept of this tangent line is when the graph is at y=0.    this rounds off to  .choice c.

(the column on the right side has numbers 1-4 as well)

from left column to the right marching definition column:
1=2
2=4
3=1
4=3