A、<span style=";font-family:宋体;font-size:16px"> t</span><sub><span style=";font-family:宋体;font-size:16px;vertical-align:sub">1</span></sub><span style=";font-family:宋体;font-size:16px">= t</span><sub><span style=";font-family:宋体;font-size:16px;vertical-align:sub">2</span></sub><span style=";font-family:宋体;font-size:16px">；</span></p><p></p>
B、<span style=";font-family:宋体;font-size:16px">t</span><sub><span style=";font-family:宋体;font-size:16px;vertical-align:sub">1</span></sub><span style=";font-family:'Times New Roman';font-size:16px"><</span><span style=";font-family:宋体;font-size:16px">t</span><sub><span style=";font-family:宋体;font-size:16px;vertical-align:sub">2</span></sub><span style=";font-family:宋体;font-size:16px">；</span></p><p></p>
C、<span style=";font-family:宋体;font-size:16px"> t</span><sub><span style=";font-family:宋体;font-size:16px;vertical-align:sub">1</span></sub><span style=";font-family:'Times New Roman';font-size:16px">></span><span style=";font-family:宋体;font-size:16px"> t</span><sub><span style=";font-family:宋体;font-size:16px;vertical-align:sub">2</span></sub><span style=";font-family:宋体;font-size:16px">；</span></p><p></p>
D、<span style=";font-family:宋体;font-size:16px">无法判断</span></p><p></p>