Koi’s Yummy Burgers delivery times

Koi’s Yummy Burgers claims that 90% of its orders are delivered within 10 minutes of the time the order is placed. A sample of 100 orders revealed that 82 were delivered within the promised time. At the .05 significance level, can we conclude that 90% of the orders are delivered in less than 10 minutes?

43. What test is most appropriate for this problem?
A. Z-test of means
B. Z-test of proportions
C. T-test
D. Chi-square – goodness of fit
E. Chi-square – test of independence
F. ANOVA – single factor

44. What is the null hypothesis?
A. H0: π = .9
B. H0: π ≠ .9
C. H0: π ≥ .9
D. H0: π ≤ .9
E. H0: μ1 = μ2

45. What is your decision?
A. Ho is accepted. More than 90% of the customers receive their orders in less than 10 minutes.
B. Ho is accepted. More than 90% of the customers receive their orders in more than 10 minutes.
C. Ho is rejected. More than 90% of the customers receive their orders in less than 10 minutes.
D. Ho is rejected. More than 90% of the customers receive their orders in more than 10 minutes.
E. Something else.