题目

Scientists may one day be able to destroy viruses in the same way that opera singers break wine glasses. New research mathematically determined the frequencies at which simple viruses could be shaken to death.The capsid (壳) of a virus is something like the shell of a turtle, said physicist Otto Sankey of Arizona State University. “If the shell can be damaged by mechanical vibrations (震动), the virus can be destroyed.”Recent experimental evidence has shown that laser (激光) pulses with the right frequency can kill certain viruses. However, locating these resonant (共振的) frequenc附加题：（1）计算：1a+2a= ；（2）如图，已知∠1=65°15'，∠2=78°30'，求∠1+∠2和∠3．