a:1:{i:0;a:13:{s:2:"id";s:3:"486";s:7:"answer1";s:250:"<p><img class="latex" src="https://chart.googleapis.com/chart?cht=tx&amp;chf=a,s,000000|bg,s,FFFFFF00&amp;chl=A%20%5Csetminus%20B%20%3D%20%5C%7B4%20%5C%7D%2C%5C%20A%20%5Ccap%20B%20%3D%20%5C%7B4%20%5C%7D" alt="A \setminus B = \{4 \},\ A \cap B = \{4 \";s:7:"answer2";s:250:"<p><img class="latex" src="https://chart.googleapis.com/chart?cht=tx&amp;chf=a,s,000000|bg,s,FFFFFF00&amp;chl=A%20%5Csetminus%20B%20%3D%20%5C%7B4%20%5C%7D%2C%5C%20A%20%5Ccap%20B%20%3D%20%5Cemptyset" alt="A \setminus B = \{4 \},\ A \cap B = \emptyset"";s:7:"answer3";s:250:"<p><img class="latex" src="https://chart.googleapis.com/chart?cht=tx&amp;chf=a,s,000000|bg,s,FFFFFF00&amp;chl=A%20%5Csetminus%20B%20%3D%20%5C(4%3B%5Cinfty%20%5C)%2C%5C%20A%20%5Ccap%20B%20%3D%20%5C%7B4%20%5C%7D" alt="A \setminus B = \(4;\infty \),\ A ";s:7:"answer4";s:250:"<p><img class="latex" src="https://chart.googleapis.com/chart?cht=tx&amp;chf=a,s,000000|bg,s,FFFFFF00&amp;chl=A%20%5Csetminus%20B%20%3D%20%5C(4%3B%5Cinfty%20%5C)%2C%5C%20A%20%5Ccap%20B%20%3D%20%5Cemptyset" alt="A \setminus B = \(4;\infty \),\ A \cap ";s:7:"answer5";s:0:"";s:7:"answer6";s:0:"";s:7:"answer7";s:0:"";s:7:"answer8";s:0:"";s:7:"answer9";s:0:"";s:8:"answer10";s:0:"";s:4:"good";s:10:"0010000000";s:8:"question";s:4:"1746";}}