Evan is organizing textbooks on his bookshelf. He has an English textbook, a biology textbook, a physics textbook, and a writing textbook. How many different ways can he line the textbooks up on his bookshelf?

Atype of plant is introduced into an ecosystem and quickly begins to take over. a scientist counts the number of plants after mmonths and develops the equation p(m)= 19.3(1.089)^m to model the situation. most recently, the scientist counted 138 plants. assuming there are no limiting factors to the growth of the plants, about how many months have passed since the plants werefirst introduced? a)o 6.1b)0.6.6c)10 72d)o 23.1