Focal length of each part when a convex lens is cut into two equal halves along the vertical axis

The same question, asked 2 times: 11 May 2024 S2, 15 Apr 2026 S1. Every wording below, oldest first.

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Question 1
11 May 2024 S2
3 $A double convex lens of focal length 'f' is cut into two equal parts along the vertical axis. The focal length of each part will be$
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Question 2
15 Apr 2026 S1
140 $An equiconvex lens of focal length F is cut in to two equal parts along the vertical axis. The focal length of each part will be$
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