Final answer:
The error in the given sentence is 'Yr', which should be 'you're' or 'you are'. To reduce sampling error, one can increase the sample size. The ±3 percent sampling error indicates the confidence range around the poll result.
Step-by-step explanation:
The error in the sentence "Hey yr, can you please give an idea as to what could be the approx placement % this season?" is option b. Yr. The abbreviation 'yr' should be replaced with the word 'you're' or 'you are' to create a more proper and grammatically correct sentence.
To address part d of your question, if one wants to lower the sampling error, a typical approach would be to increase the sample size. A larger sample size generally leads to a smaller sampling error because it is more likely to accurately reflect the characteristics of the entire population.
Regarding part e, the ±3 percent represents the range within which the true value is expected to lie with a certain level of confidence. For example, if a poll shows that 50% of respondents favor a certain candidate, with a ±3 percent sampling error, we can be reasonably confident that the true percentage of favorability lies between 47% and 53%.