Answer: The point estimate of the population proportion is . 485.
The margin of error is 0.273.
Step-by-step explanation:
Confidence interval for population proportion(p): 
sample proportion ± Margin of error
Given:  Lower bound of confidence interval  = 0.212
Upper bound = 0.758
⇒sample proportion - Margin of error=0.212  (i)
sample proportion + Margin of error= 0.758  (ii)
Adding (i) and (ii) , we get
2(sample proportion) =0.970
⇒ sample proportion = 0.970÷2= 0.485
Since sample proportion is the point estimate of the population proportion. 
So, the point estimate of the population proportion=  0.485
Now put sample proportion =0.485 in (ii), we get
0.485+ Margin of error= 0.758
⇒  Margin of error= 0.758 - 0.485 =0.273
i.e. The margin of error is 0.273.