Answer: The correct answer 1.404
Step-by-step explanation:
[tex]\log4^3=0.792[/tex]
[tex]\log4^{21}=2.196[/tex]
[tex]\log4^{21}=\log(4^{3}\times4^{7})=\log4^3+\log4^7=2.196[/tex]
[tex]\log4^7=2.196-\log4^3=2.196-0.792=1.404[/tex]
The correct value of [tex]\log4^7[/tex] is 1.404. so the correct option from the given option is 1.404.