Answer: hello your question is incomplete attached below is the complete question
answer : 
a) 85.0
b) 27.4 
c) (82.26, 87.74 )
Explanation:
Given data :
95% confidence interval 
x ( mean ) = 85
s = 8.8 
n ( sample size ) = 42 
 using t-distribution
a) calculate the point estimate 
The point estimate = 85.0 given that a sample mean is the same as a point estimate of the sample population
b) calculate the Margin of error 
df = 42 - 1 = 41
∝ = 0.05 
critical value ( T ∝/2 , 41 ) = 2.02
hence ; margin of error ( E ) 
= 2.74 ( using margin of error calculator ) 
c) The 95% confidence interval 
 = 85 ± 2.74 
 (82.26, 87.74 )