If Smiley weighs more than Jill's car, Smiley is too heavy for the bridge.
The salt will wash into the rivers and eventually the ocean. Too much salt in a freshwater system can be deadly to the wildlife. Ultimately, it will end up in the ocean, where it will have negligible impact. The real damage will be to any river systems it's washed into.
Tropical places are hot because the humidity coming from the moisture of the plants and water are heated by the sun on the top layer of the tropical zone. The climate varies little in rain forest. There are five layers in the tropic trees so it's so thick that barely any light come through. This is also why vines grow up the trees so they can reach the sunlight to get nutrients. Also, the tropics are near the equator and that also causes the heat. The polars are cold because they barely get any sun heat to melt the snow or warm it up. The polars are melting due to certain chemicals and gasses in the atmosphere. also known as global warming. Hope that was helpful!
Is this a multiple choice question?