Why do vaccine makers have to guess which flu strains will be active months before the flu season begins?

Me i’m in need of answerering this

Ineed asap plzzz why is the mountain goat known as the poor man's cow? a. it is a cheap source of food. b. it is smaller than a cow. c. it looks like a cow.

In at least 150 words, discuss the comparison described in the figurative language and how the connotative language reinforces the symbol. certainly the utmost rim of my first dome was filled with the tumultuous impression of soldiers marching to death for freedom's sake, of pioneers streaming westward to establish self-government in yet another sovereign state. only the great dome of st. peter's itself has ever clutched my heart as did that modest curve which had sequestered from infinitude in a place small enough for my child's mind, the courage and endurance which i could not comprehend so long as it was lost in "the void of unresponsible space" under the vaulting sky itself.