MCS 005 ACTUAL EXAM PAPER 2026
QUESTIONS WITH ANSWERS GRADED A+
◍ One-time pad.
Answer: _____ is considered to be unbreakable since it only uses its cipher
code once.
◍ 128.
Answer: The key size used with XTEA is _____ bits.A. 128B. 256C. 2048
◍ Shawn's public key.
Answer: If Shawn employs public key cryptography to send Sue a digitally
signed message, which key will Sue use to verify the message?A. Sue's
private keyB. Shawn's public keyC. Sue's public key
◍ Initialization.
Answer: Certificate distribution takes place in the _____ stage of certificate
management.A. InitializationB. IssuedC. Cancellation
◍ Cut-and-paste.
Answer: A ___ attack is where an attacker mixes parts of two different
encrypted messages and is able to create a new message. This message is
likely to make no sense but may trick the receiver into doing something that
helps the intruder.A. ReplayB. Man-in-the-middleC. Cut-and-paste
◍ Online Certificate Status Protocol (OCSP).
Answer: An alterative to the CRL is to use_____, an online service used to
check the validity of a certificate.A. OSCPB. OCSPC. OWASP
◍ RC5.
Answer: _____ is a symmetric block cipher that uses block sizes of 32, 64,
or 128 bits and boasts a variable key size up to 2048 bits.A. RC2B. RC4C.
RC5
,◍ Mono-alphabetic.
Answer: _____ substitution is where a single mapping from our alphabet to
a cipher alphabet is created.A. Mono-alphabeticB. PolyalphabeticC.
Pseudo-random
◍ HFO-1234yf can be used in:.
Answer: Any light vehicle with an air conditioning system designed to use it
◍ Section 609 of the Clean Air Act requires that recovery/recycling
equipment:.
Answer: Must be registered with the EPA
◍ 128-bit key size; 64-bit IV.
Answer: Enocoro operates with a key size of ______ bits and an
initialization vector (IV) of _____ bits.A. 80; 80B. 128; 64C. 80; 64
◍ Chaskey.
Answer: _____ is a lightweight cryptography method for signing messages
(MAC). It boasts a relatively undemanding hardware implementation (only
~3,333 gates required at 1MHz clock rate) making it suitable for IoT
implementation.
◍ miners.
Answer: Bitcoin transactions will be captured by ______ who will compile a
list of the latest transactions.A. miners B. bankersC. administrators
◍ Man-in-the-middle.
Answer: A ___ attack occurs when an attacker is hidden between two parties
and impersonates each of them to the other.A. Time resettingB.
Man-in-the-middleC. Brute force
◍ Block, Stream.
Answer: The two types of symmetric ciphers are _____ and _____A. Block,
StreamB. CTR, DESC. Active, Passive
◍ Output Feedback (OFB).
Answer: With the _____ block cipher mode, the encrypted version of the IV
, produced in the first stage (during processing of the first block) is fed into
the second stage and encrypted. A. OFBB. CTRC. CFB
◍ 10000.
Answer: Solve by applying the binary AND function.1101110000A.
11011B. 10000C. 01011
◍ CA.
Answer: A CRL must be published by the _____ who originally generated
the targeted certificates.A. RAB. CAC. Certificate owner
◍ PKCS #5.
Answer: PKCS #__ is a standard used for password-based encryption.A. 1B.
5C. 7
◍ Block cipher modes.
Answer: _____ are used to manage how blocks of data are processed in
symmetric encryption.A. Stream ciphersB. Block cipher modesC. Padding
◍ 128 bits.
Answer: AES when operating with 10 rounds uses what key size?A. 128
bitsB. 192 BitsC 256 bits
◍ When using an HFC-134a refrigerant recovery machine, after competing the
first recovery process, how long must you wait, then check the machine's
gauges for a rise in pressure above vacuum, which would indicate that the
system still contains some refrigerant?.
Answer: 5 minutes
◍ PEM.
Answer: Which encoding scheme for x.509 certificates supports Base64 and
ASCII formats?A. DERB. PEMC. MAC
◍ How much moisture is removed from a mobile A/C system during a typical
evacuation?.
Answer: Possibly none
◍ 128.
QUESTIONS WITH ANSWERS GRADED A+
◍ One-time pad.
Answer: _____ is considered to be unbreakable since it only uses its cipher
code once.
◍ 128.
Answer: The key size used with XTEA is _____ bits.A. 128B. 256C. 2048
◍ Shawn's public key.
Answer: If Shawn employs public key cryptography to send Sue a digitally
signed message, which key will Sue use to verify the message?A. Sue's
private keyB. Shawn's public keyC. Sue's public key
◍ Initialization.
Answer: Certificate distribution takes place in the _____ stage of certificate
management.A. InitializationB. IssuedC. Cancellation
◍ Cut-and-paste.
Answer: A ___ attack is where an attacker mixes parts of two different
encrypted messages and is able to create a new message. This message is
likely to make no sense but may trick the receiver into doing something that
helps the intruder.A. ReplayB. Man-in-the-middleC. Cut-and-paste
◍ Online Certificate Status Protocol (OCSP).
Answer: An alterative to the CRL is to use_____, an online service used to
check the validity of a certificate.A. OSCPB. OCSPC. OWASP
◍ RC5.
Answer: _____ is a symmetric block cipher that uses block sizes of 32, 64,
or 128 bits and boasts a variable key size up to 2048 bits.A. RC2B. RC4C.
RC5
,◍ Mono-alphabetic.
Answer: _____ substitution is where a single mapping from our alphabet to
a cipher alphabet is created.A. Mono-alphabeticB. PolyalphabeticC.
Pseudo-random
◍ HFO-1234yf can be used in:.
Answer: Any light vehicle with an air conditioning system designed to use it
◍ Section 609 of the Clean Air Act requires that recovery/recycling
equipment:.
Answer: Must be registered with the EPA
◍ 128-bit key size; 64-bit IV.
Answer: Enocoro operates with a key size of ______ bits and an
initialization vector (IV) of _____ bits.A. 80; 80B. 128; 64C. 80; 64
◍ Chaskey.
Answer: _____ is a lightweight cryptography method for signing messages
(MAC). It boasts a relatively undemanding hardware implementation (only
~3,333 gates required at 1MHz clock rate) making it suitable for IoT
implementation.
◍ miners.
Answer: Bitcoin transactions will be captured by ______ who will compile a
list of the latest transactions.A. miners B. bankersC. administrators
◍ Man-in-the-middle.
Answer: A ___ attack occurs when an attacker is hidden between two parties
and impersonates each of them to the other.A. Time resettingB.
Man-in-the-middleC. Brute force
◍ Block, Stream.
Answer: The two types of symmetric ciphers are _____ and _____A. Block,
StreamB. CTR, DESC. Active, Passive
◍ Output Feedback (OFB).
Answer: With the _____ block cipher mode, the encrypted version of the IV
, produced in the first stage (during processing of the first block) is fed into
the second stage and encrypted. A. OFBB. CTRC. CFB
◍ 10000.
Answer: Solve by applying the binary AND function.1101110000A.
11011B. 10000C. 01011
◍ CA.
Answer: A CRL must be published by the _____ who originally generated
the targeted certificates.A. RAB. CAC. Certificate owner
◍ PKCS #5.
Answer: PKCS #__ is a standard used for password-based encryption.A. 1B.
5C. 7
◍ Block cipher modes.
Answer: _____ are used to manage how blocks of data are processed in
symmetric encryption.A. Stream ciphersB. Block cipher modesC. Padding
◍ 128 bits.
Answer: AES when operating with 10 rounds uses what key size?A. 128
bitsB. 192 BitsC 256 bits
◍ When using an HFC-134a refrigerant recovery machine, after competing the
first recovery process, how long must you wait, then check the machine's
gauges for a rise in pressure above vacuum, which would indicate that the
system still contains some refrigerant?.
Answer: 5 minutes
◍ PEM.
Answer: Which encoding scheme for x.509 certificates supports Base64 and
ASCII formats?A. DERB. PEMC. MAC
◍ How much moisture is removed from a mobile A/C system during a typical
evacuation?.
Answer: Possibly none
◍ 128.
