diff --git a/assets/section_2.3_1686916498071_0.edn b/assets/section_2.3_1686916498071_0.edn
index 7c3e87f..3eef5c1 100644
--- a/assets/section_2.3_1686916498071_0.edn
+++ b/assets/section_2.3_1686916498071_0.edn
@@ -9,5 +9,17 @@
                           :rects (),
                           :page 6},
                :content {:text "[:span]", :image 1686916764282},
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+              {:id #uuid "648c5298-fb84-4e9c-b816-7df1a7ad9a66",
+               :page 16,
+               :position {:bounding {:x1 41.16666603088379,
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diff --git a/assets/section_2.3_1686916498071_0/16_648c5298-fb84-4e9c-b816-7df1a7ad9a66_1686917782356.png b/assets/section_2.3_1686916498071_0/16_648c5298-fb84-4e9c-b816-7df1a7ad9a66_1686917782356.png
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diff --git a/pages/hls__section_2.3_1686916498071_0.md b/pages/hls__section_2.3_1686916498071_0.md
index fdaa23c..51eea4d 100644
--- a/pages/hls__section_2.3_1686916498071_0.md
+++ b/pages/hls__section_2.3_1686916498071_0.md
@@ -7,4 +7,11 @@ file-path:: ../assets/section_2.3_1686916498071_0.pdf
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+  hl-stamp:: 1686916764282
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+  hl-color:: yellow
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diff --git a/pages/总复习2023t1.md b/pages/总复习2023t1.md
index e77db88..a71dd1f 100644
--- a/pages/总复习2023t1.md
+++ b/pages/总复习2023t1.md
@@ -2721,7 +2721,7 @@
 					- Mathematical Expectation and Variance ![section 2.3.pdf](../assets/section_2.3_1686916498071_0.pdf)
 						- Expectation
 							- ((648c4e9e-5515-4da3-bc6b-39d6969f5f14))
-							-
+								- Example
 			- LATER 学积分
 			  :LOGBOOK:
 			  CLOCK: [2023-06-03 Sat 17:05:07]--[2023-06-03 Sat 17:05:08] =>  00:00:01