松焦油的作用。
参考答案：
与橡胶互溶性好，工艺性能较好，有补强性，低温下有迟延硫化防止焦烧的作用，会加速橡胶的老化。主要用于NR和SBR。
—Wow, you look good. Your hair looks fantastic. You’re such a wonderful friend. You’re so generous. I’ve always liked you.
—________! Get to the point. I haven’t got food all day.
A．Enough
B．Thanks
C．Really
D．Rubbish
同一体积的物体比容越大表示物体越轻，密度越大表示物体越重。
uch a wonderful friend. You’re so generous. I’ve always liked you.
ood all day.