<p>If I am a junior appling for econ major. I am taking Econ 100b this semester. So do I have to take econ 100a this spring? Or can I take the econ100a next Fall?</p>
<p>you can take econ 100a whenever you want
The major only requires that you have one part of the 100 series when you declare :D</p>
<p>You can but be aware that 100a is helpful for some econ electives.</p>
<p>^^ Truth 10char</p>