Rosalyn's arms felt tired and fatigued after she held her cousin's baby for a few minutes. what area of fitness does she need to improve?

I found the missing choices, these are: 
Cardiorespiratory endurance
Body composition
Flexibility
Muscular strength

Rosalyn's area of fitness that needs to improve is MUSCULAR STRENGTH. 

Muscular strength is defined as the amount of force a muscle can produce with a single maximal effort. In Rosalyn's case, she needs to develop her arm muscles to enable her to hold her cousin's baby without feeling any fatigue.

Yep i just took this test

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.