Mystery #2 (yellow single flower)

Another one, if anyone is interested. Smaller, more delicate than the holly. See follow-up for leaf shape.

Click image to enlarge

Leaf shape

Reply from Kevin Pfeiffer

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-K

Click image to enlarge

mystery plant #2

Reply from Kathy C

Hi, Kevin,
I am pretty certain this is Buttercup - probably Ranunculus repens. Considered a weed by some, but such a sweet flower. We used to hold them to our chins as children to see if our chin looked yellow (from the yellow colour reflecting off our chin) - if it did, you definitely like butter! We always did!
Kathy C.