What is the correct verb there (is, are) a number of homeless cats

The excerpt is from a longer essay on huckleberry finn by mark twain. what kind of support is used to develop the writer's main idea regarding how twain brought his characters to life?

Read this excerpt from leah missbach day's foreword to wheels of change. bicycles have long played a role in my life. as a young woman, i rode one year-round before i had a car. but it was later in adulthood that the bicycle became more than a source of transportation for me. the bicycle actually began to truly shape the way i saw the world. what is the author's purpose for including this in the foreword?

We will be learning about animals that live in the arctic. your assignment is to find information about one animal in the arctic. be sure that you find the following information about the animal: average height and weight, appearance, diet, shelter, mating habits, and any other interesting or important facts. we will use the information that you gather in the research with an in-class project. be sure to keep track of your sources; your final project will require a works cited page. in an internet search engine, which group of keywords is most appropriate for this assignment? a) project, arctic, diet b) arctic, animals, facts c) cold, appearance, animals d) average height and weight, one animal