Select all that apply. Which of the following factors affect pathogenicity of a microorganism? 

Which of the following would the best choice for treating a life-threatening bacterial infection?

#21: 

#20: Let be a twice-differentiable, increasing function of . If and , which of the following must be true on the interval ?

#24: Let be the function given by

#18: Let be the function defined by . What is the approximation for found by using the line tangent to the graph of at the point ?

#13: For time

#28:

#14: If is a differentiable function and

#25: Which of the following is a solution to the differential equation