Answer:
B, D and E
Step-by-step explanation:
Using the rules of exponents/ radicals
[tex]a^{-m}[/tex] = [tex]\frac{1}{a^{m} }[/tex]
[tex]a^{\frac{1}{2} }[/tex] = [tex]\sqrt{a}[/tex]
Given
[tex]49^{-\frac{1}{2} }[/tex] = [tex]\frac{1}{49^{\frac{1}{2} } }[/tex] → E
= [tex]\frac{1}{\sqrt{49} }[/tex] → B
= [tex]\frac{1}{7}[/tex] → D
