The stem of aquatic plants is covered with waxy substance why

Nasa scientists must work together to make sure that everything is correct and accounted for when launching a shuttle. besides a physicist, what other type of scientist would be in making sure that the shuttle has the appropriate type and amount of fuel to reach its destination?

What is the problem in this article? what solution does the article propose?

Communication and transportation have improved as a result of scientific advancements. select the best answer from the choices provided of mark this and return save and exit next