The C-10 practice test that actually gets you ready.

1. 1. C-10 Trade exam · Planning & Estimating

   Using the optional multifamily method, a 20-unit apartment building applies a Table 220.84 demand factor of:

   • A. 45 percent
   • B. 43 percent
   • C. 41 percent
   • D. 38 percent
   Show the answer

   Answer: D. 38 percent

   Table 220.84(B) gives 38 percent for 18-20 dwelling units.

   Reference: CEC Table 220.84

2. 2. C-10 Trade exam · Rough Wiring

   Under its scope section 725.1, Article 725 of the 2025 CEC covers:

   • A. electric light and power circuits
   • B. power-limited circuits, including power-limited remote-control and signaling circuits, that are not an integral part of a device or of utilization equipment
   • C. services
   • D. motors
   Show the answer

   Answer: B. power-limited circuits, including power-limited remote-control and signaling circuits, that are not an integral part of a device or of utilization equipment

   725.1 Scope: this article covers power-limited circuits, including power-limited remote-control and signaling circuits, that are not an integral part of a device or of utilization equipment.

   Reference: CEC Article 725 (2023 rewrite) / Article 724 (Class 1)

3. 3. C-10 Trade exam · Finish Wiring & Trim

   A 15/20 A receptacle in a WET location must have:

   • A. any standard cover
   • B. an enclosure that is weatherproof whether or not the attachment plug cap is inserted
   • C. no cover
   • D. a metal blank plate
   Show the answer

   Answer: B. an enclosure that is weatherproof whether or not the attachment plug cap is inserted

   Receptacles of 15 and 20 amperes, 125 and 250 volts, in a wet location must have an enclosure that is weatherproof whether or not the attachment plug cap is inserted. An outlet box hood used for this must be listed and identified as extra-duty (CEC 406.9(B)).

   Reference: CEC 406.9(B)(1)

4. 4. C-10 Trade exam · Startup, Troubleshooting & Maintenance

   Using I = E ÷ R, a 240 V heating element with a resistance of 16 ohms draws a current of:

   • A. 7.5 A
   • B. 15 A
   • C. 30 A
   • D. 3,840 A
   Show the answer

   Answer: B. 15 A

   I = E ÷ R = 240 V ÷ 16 ohms = 15 A.

   Reference: Arithmetic

5. 5. C-10 Trade exam · Safety

   Under 2405.4, the written description of an employer's assured equipment grounding conductor program must be:

   • A. Kept only at the main office
   • B. Filed with the serving utility
   • C. Available at the job site for inspection and copying
   • D. Mailed to each worker's home
   Show the answer

   Answer: C. Available at the job site for inspection and copying

   2405.4: the written description of the program, including the employer's specific procedures, shall be available at the job site for inspection and copying by Cal/OSHA and any affected employee.

   Reference: T8 2405.4

6. 6. Law & Business exam · Contracts & Change Orders

   In addition to refunding the buyer's money within the 10-day window, the seller must also:

   • A. Retain a 10% restocking fee
   • B. Record a mechanics lien on the property
   • C. Report the cancellation to the CSLB
   • D. Cancel any security interest arising out of the transaction
   Show the answer

   Answer: D. Cancel any security interest arising out of the transaction

   The Notice of Cancellation required by Civil Code 1689.7 tells the buyer that payments will be returned within 10 days following receipt by the seller of the cancellation notice, and any security interest arising out of the transaction will be canceled.

   Reference: Civil Code §1689.7

7. 7. Law & Business exam · Bonds, Insurance & Licensing

   The contractor license bond increased to its current amount effective:

   • A. it never changed
   • B. January 1, 2023
   • C. 2010
   • D. 2026
   Show the answer

   Answer: B. January 1, 2023

   The bond increased to $25,000 effective January 1, 2023.

   Reference: SB 607 (B&P §7071.6)

8. 8. Law & Business exam · Employment, Payroll & Safety

   The version of BPC 7125 that limits the no-employee workers' compensation exemption to a joint venture with no employees becomes operative on:

   • A. January 1, 2023
   • B. January 1, 2026
   • C. January 1, 2027
   • D. January 1, 2028
   Show the answer

   Answer: D. January 1, 2028

   BPC 7125, in the version whose exemption covers only a licensee organized as a joint venture under Section 7029 that has no employees, states: this section shall become operative on January 1, 2028.

   Reference: SB 216 (2022) as amended by SB 1455 (2024)

9. 9. Law & Business exam · Estimating, Bidding & Project Management

   On California PUBLIC works projects, retention is generally capped at:

   • A. 10 percent
   • B. 5 percent
   • C. 20 percent
   • D. there is no cap
   Show the answer

   Answer: B. 5 percent

   Public Contract Code 7201(b)(1): retention withheld from any payment on a public work shall not exceed 5 percent of the payment, and total retention shall not exceed 5 percent of the contract price.

   Reference: CA Public Contract Code §7201

10. 10. Law & Business exam · Lien Law

    Before filing a petition to release a lien that was not timely foreclosed, the owner must first:

    • A. Pay the disputed amount into court in full
    • B. Wait a full year from recording of the lien
    • C. Give the claimant a demand to release the lien at least 10 days before filing
    • D. Obtain a completed jury trial on the debt
    Show the answer

    Answer: C. Give the claimant a demand to release the lien at least 10 days before filing

    Section 8482 bars an owner from petitioning for a release order unless, at least 10 days before filing, the owner gave the claimant notice demanding that the claimant execute and record a release of the lien.

    Reference: CA Civil Code §8482

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