the task is to answer the following questions in one paragraph

Scenario 3
You are in Times Square in New York City. A stopped van a couple of blocks away blows up (it is a dirty bomb with about 5 kg of Strontium 90 that was smuggled from a Russian Radionuclide Thermoelectric Generator but you don’t know it at the time). There are fragments of material dropping around you. What can you do?
• What would your reaction be?
• How does the strontium 90 threaten you?
• What are its effects?
• What are the risks?
• How can you protect yourself?