Words coded as digits in scrambled order: find a letter's code from shared letters

This type of question, asked 3 times: 26 Oct 2023 Tier II, 18 Jan 2025 Tier II, 20 Jan 2025 Tier II. All 3 questions below, oldest first.

Try each one first, then open its answer.

Question 1
26 Oct 2023 Tier II
59 $In a certain code language, ‘CARD’ is coded as ‘7359’, ‘SERV’ is coded as ‘1256’and ‘PACK’ is coded as ‘8497’. What is the code for ‘D’ in the given code language?$
Tap an option to check your answer.
Question 2
18 Jan 2025 Tier II
45 $In a certain code language, ‘POSE’ is coded as ‘3517’ and ‘SILK’ is coded as ‘4638’. What is the code for ‘S’ in the given code language?$
Tap an option to check your answer.
Question 3
20 Jan 2025 Tier II
35 $In a certain code language, ‘CURB’ is coded as ‘3517’ and ‘BOAT’ is coded as ‘4638’. What is the code for ‘B’ in the given code language?$
Tap an option to check your answer.

Question 1