The image appears to be rotated, and the text is aligned vertically. Let me analyze and extract the text content from the image for further analysis.

Extracted Text:

From the image, I can see the following:

Text:

• "If ∠AOB = 100° then ∠ACB = ?"
• "Two circles touch externally. A common tangent AB touches the two circles at A and B respectively."

Problem Analysis:

1. First Problem:

   • Given: $\angle AOB = 100^\circ$
   • Find: $\angle ACB$

2. Second Problem:

   • Two circles touch externally, and a common tangent $AB$ touches the two circles at points $A$ and $B$, respectively.
   • Find the relationship or value based on this configuration.

Would you like me to solve these problems?