Problem 15-5 the reference desk of a university library receives requests for assistance. assume that a poisson probability distribution with an arrival rate of 10 requests per hour can be used to describe the arrival pattern and that service times follow an exponential probability distribution with a service rate of 12 requests per hour. what is the probability that no requests for assistance are in the system? if required, round your answer to four decimal places.

What is the ratio of the change in y-values to the change in x-values for this function? a) 1: 13 b) 2: 5 c) 5: 2 d) 13: 1

Given: ab ≅ cd and ad ≅ bc prove: abcd is a parallelogram. statements reasons 1. ab ≅ cd; ad ≅ bc 1. given 2. ac ≅ ac 2. reflexive property 3. △adc ≅ △cba 3. ? 4. ∠dac ≅ ∠bca; ∠acd ≅ ∠cab 4. cpctc 5. ∠dac and ∠bca are alt. int. ∠s; ∠acd and ∠cab are alt. int. ∠s 5. definition of alternate interior angles 6. ab ∥ cd; ad ∥ bc 6. converse of the alternate interior angles theorem 7. abcd is a parallelogram 7. definition of parallelogram what is the missing reason in step 3? triangle angle sum theorem sas congruency theorem sss congruency theorem cpctc

One x-intercept for a parabola is at the point (1,0). use the factor method to find x-intercept for the parabola defined by the equation y=-3x^2+5x+2