Conversion (%)
	A	B	C
1	70	85	87
2	72	86	85
3	71	86	86
4	71	84	86
5	73	88	84

a) Is there a difference in the expected value of catalysts A and C?

b) Can we believe that the expected value of catalyst C is 85?

Do not forget about checking whether the assumptions about the residuals are fulfilled.